diff --git a/Doc/library/zipfile.rst b/Doc/library/zipfile.rst
index 1c81262..3ca20de 100644
--- a/Doc/library/zipfile.rst
+++ b/Doc/library/zipfile.rst
@@ -382,7 +382,10 @@
 
    Instances have one method in addition to those of :class:`ZipFile` objects:
 
-   .. method:: PyZipFile.writepy(pathname, basename='')
+   .. method:: PyZipFile.writepy(pathname, basename='', filterfunc=None)
+
+      .. versionadded:: 3.4
+         The *filterfunc* parameter.
 
       Search for files :file:`\*.py` and add the corresponding file to the
       archive.
@@ -404,7 +407,10 @@
       package directory, then all :file:`\*.py[co]` are added under the package
       name as a file path, and if any subdirectories are package directories,
       all of these are added recursively.  *basename* is intended for internal
-      use only.  The :meth:`writepy` method makes archives with file names like
+      use only.  When *filterfunc(pathname)* is given, it will be called for every
+      invocation. When it returns a False value, that path and its subpaths will
+      be ignored.
+      The :meth:`writepy` method makes archives with file names like
       this::
 
          string.pyc                   # Top level name
diff --git a/Doc/whatsnew/3.4.rst b/Doc/whatsnew/3.4.rst
index 2b68d86..c02b9cc 100644
--- a/Doc/whatsnew/3.4.rst
+++ b/Doc/whatsnew/3.4.rst
@@ -564,6 +564,16 @@
 
 (Contributed by Antoine Pitrou in :issue:`17741`.)
 
+
+zipfile.PyZipfile
+-----------------
+
+Add a filter function to ignore some packages (tests for instance),
+:meth:`~zipfile.PyZipFile.writepy`.
+
+(Contributed by Christian Tismer in :issue:`19274`.)
+
+
 Other improvements
 ==================
 
diff --git a/Lib/test/test_zipfile.py b/Lib/test/test_zipfile.py
index 899a3fb..4a8c1af 100644
--- a/Lib/test/test_zipfile.py
+++ b/Lib/test/test_zipfile.py
@@ -591,6 +591,28 @@
             self.assertCompiledIn('email/__init__.py', names)
             self.assertCompiledIn('email/mime/text.py', names)
 
+    def test_write_filtered_python_package(self):
+        import test
+        packagedir = os.path.dirname(test.__file__)
+
+        with TemporaryFile() as t, zipfile.PyZipFile(t, "w") as zipfp:
+
+            stdout = sys.stdout
+
+            # first make sure that the test folder gives error messages
+            sys.stdout = reportSIO = io.StringIO()
+            zipfp.writepy(packagedir)
+            reportStr = reportSIO.getvalue()
+            self.assertTrue('SyntaxError' in reportStr)
+
+            # then check that the filter works
+            sys.stdout = reportSIO = io.StringIO()
+            zipfp.writepy(packagedir, filterfunc=lambda whatever:False)
+            reportStr = reportSIO.getvalue()
+            self.assertTrue('SyntaxError' not in reportStr)
+
+            sys.stdout = stdout
+
     def test_write_with_optimization(self):
         import email
         packagedir = os.path.dirname(email.__file__)
@@ -600,7 +622,7 @@
         ext = '.pyo' if optlevel == 1 else '.pyc'
 
         with TemporaryFile() as t, \
-                 zipfile.PyZipFile(t, "w", optimize=optlevel) as zipfp:
+             zipfile.PyZipFile(t, "w", optimize=optlevel) as zipfp:
             zipfp.writepy(packagedir)
 
             names = zipfp.namelist()
@@ -733,25 +755,25 @@
     def test_extract_hackers_arcnames_windows_only(self):
         """Test combination of path fixing and windows name sanitization."""
         windows_hacknames = [
-                (r'..\foo\bar', 'foo/bar'),
-                (r'..\/foo\/bar', 'foo/bar'),
-                (r'foo/\..\/bar', 'foo/bar'),
-                (r'foo\/../\bar', 'foo/bar'),
-                (r'C:foo/bar', 'foo/bar'),
-                (r'C:/foo/bar', 'foo/bar'),
-                (r'C://foo/bar', 'foo/bar'),
-                (r'C:\foo\bar', 'foo/bar'),
-                (r'//conky/mountpoint/foo/bar', 'foo/bar'),
-                (r'\\conky\mountpoint\foo\bar', 'foo/bar'),
-                (r'///conky/mountpoint/foo/bar', 'conky/mountpoint/foo/bar'),
-                (r'\\\conky\mountpoint\foo\bar', 'conky/mountpoint/foo/bar'),
-                (r'//conky//mountpoint/foo/bar', 'conky/mountpoint/foo/bar'),
-                (r'\\conky\\mountpoint\foo\bar', 'conky/mountpoint/foo/bar'),
-                (r'//?/C:/foo/bar', 'foo/bar'),
-                (r'\\?\C:\foo\bar', 'foo/bar'),
-                (r'C:/../C:/foo/bar', 'C_/foo/bar'),
-                (r'a:b\c<d>e|f"g?h*i', 'b/c_d_e_f_g_h_i'),
-                ('../../foo../../ba..r', 'foo/ba..r'),
+            (r'..\foo\bar', 'foo/bar'),
+            (r'..\/foo\/bar', 'foo/bar'),
+            (r'foo/\..\/bar', 'foo/bar'),
+            (r'foo\/../\bar', 'foo/bar'),
+            (r'C:foo/bar', 'foo/bar'),
+            (r'C:/foo/bar', 'foo/bar'),
+            (r'C://foo/bar', 'foo/bar'),
+            (r'C:\foo\bar', 'foo/bar'),
+            (r'//conky/mountpoint/foo/bar', 'foo/bar'),
+            (r'\\conky\mountpoint\foo\bar', 'foo/bar'),
+            (r'///conky/mountpoint/foo/bar', 'conky/mountpoint/foo/bar'),
+            (r'\\\conky\mountpoint\foo\bar', 'conky/mountpoint/foo/bar'),
+            (r'//conky//mountpoint/foo/bar', 'conky/mountpoint/foo/bar'),
+            (r'\\conky\\mountpoint\foo\bar', 'conky/mountpoint/foo/bar'),
+            (r'//?/C:/foo/bar', 'foo/bar'),
+            (r'\\?\C:\foo\bar', 'foo/bar'),
+            (r'C:/../C:/foo/bar', 'C_/foo/bar'),
+            (r'a:b\c<d>e|f"g?h*i', 'b/c_d_e_f_g_h_i'),
+            ('../../foo../../ba..r', 'foo/ba..r'),
         ]
         self._test_extract_hackers_arcnames(windows_hacknames)
 
@@ -877,10 +899,10 @@
     def test_unsupported_version(self):
         # File has an extract_version of 120
         data = (b'PK\x03\x04x\x00\x00\x00\x00\x00!p\xa1@\x00\x00\x00\x00\x00\x00'
-        b'\x00\x00\x00\x00\x00\x00\x01\x00\x00\x00xPK\x01\x02x\x03x\x00\x00\x00\x00'
-        b'\x00!p\xa1@\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x01\x00\x00'
-        b'\x00\x00\x00\x00\x00\x00\x00\x00\x00\x80\x01\x00\x00\x00\x00xPK\x05\x06'
-        b'\x00\x00\x00\x00\x01\x00\x01\x00/\x00\x00\x00\x1f\x00\x00\x00\x00\x00')
+                b'\x00\x00\x00\x00\x00\x00\x01\x00\x00\x00xPK\x01\x02x\x03x\x00\x00\x00\x00'
+                b'\x00!p\xa1@\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x01\x00\x00'
+                b'\x00\x00\x00\x00\x00\x00\x00\x00\x00\x80\x01\x00\x00\x00\x00xPK\x05\x06'
+                b'\x00\x00\x00\x00\x01\x00\x01\x00/\x00\x00\x00\x1f\x00\x00\x00\x00\x00')
 
         self.assertRaises(NotImplementedError, zipfile.ZipFile,
                           io.BytesIO(data), 'r')
@@ -1066,11 +1088,11 @@
     def test_unsupported_compression(self):
         # data is declared as shrunk, but actually deflated
         data = (b'PK\x03\x04.\x00\x00\x00\x01\x00\xe4C\xa1@\x00\x00\x00'
-        b'\x00\x02\x00\x00\x00\x00\x00\x00\x00\x01\x00\x00\x00x\x03\x00PK\x01'
-        b'\x02.\x03.\x00\x00\x00\x01\x00\xe4C\xa1@\x00\x00\x00\x00\x02\x00\x00'
-        b'\x00\x00\x00\x00\x00\x01\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00'
-        b'\x80\x01\x00\x00\x00\x00xPK\x05\x06\x00\x00\x00\x00\x01\x00\x01\x00'
-        b'/\x00\x00\x00!\x00\x00\x00\x00\x00')
+                b'\x00\x02\x00\x00\x00\x00\x00\x00\x00\x01\x00\x00\x00x\x03\x00PK\x01'
+                b'\x02.\x03.\x00\x00\x00\x01\x00\xe4C\xa1@\x00\x00\x00\x00\x02\x00\x00'
+                b'\x00\x00\x00\x00\x00\x01\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00'
+                b'\x80\x01\x00\x00\x00\x00xPK\x05\x06\x00\x00\x00\x00\x01\x00\x01\x00'
+                b'/\x00\x00\x00!\x00\x00\x00\x00\x00')
         with zipfile.ZipFile(io.BytesIO(data), 'r') as zipf:
             self.assertRaises(NotImplementedError, zipf.open, 'x')
 
@@ -1232,57 +1254,57 @@
 class StoredBadCrcTests(AbstractBadCrcTests, unittest.TestCase):
     compression = zipfile.ZIP_STORED
     zip_with_bad_crc = (
-            b'PK\003\004\024\0\0\0\0\0 \213\212;:r'
-            b'\253\377\f\0\0\0\f\0\0\0\005\0\0\000af'
-            b'ilehello,AworldP'
-            b'K\001\002\024\003\024\0\0\0\0\0 \213\212;:'
-            b'r\253\377\f\0\0\0\f\0\0\0\005\0\0\0\0'
-            b'\0\0\0\0\0\0\0\200\001\0\0\0\000afi'
-            b'lePK\005\006\0\0\0\0\001\0\001\0003\000'
-            b'\0\0/\0\0\0\0\0')
+        b'PK\003\004\024\0\0\0\0\0 \213\212;:r'
+        b'\253\377\f\0\0\0\f\0\0\0\005\0\0\000af'
+        b'ilehello,AworldP'
+        b'K\001\002\024\003\024\0\0\0\0\0 \213\212;:'
+        b'r\253\377\f\0\0\0\f\0\0\0\005\0\0\0\0'
+        b'\0\0\0\0\0\0\0\200\001\0\0\0\000afi'
+        b'lePK\005\006\0\0\0\0\001\0\001\0003\000'
+        b'\0\0/\0\0\0\0\0')
 
 @requires_zlib
 class DeflateBadCrcTests(AbstractBadCrcTests, unittest.TestCase):
     compression = zipfile.ZIP_DEFLATED
     zip_with_bad_crc = (
-            b'PK\x03\x04\x14\x00\x00\x00\x08\x00n}\x0c=FA'
-            b'KE\x10\x00\x00\x00n\x00\x00\x00\x05\x00\x00\x00af'
-            b'ile\xcbH\xcd\xc9\xc9W(\xcf/\xcaI\xc9\xa0'
-            b'=\x13\x00PK\x01\x02\x14\x03\x14\x00\x00\x00\x08\x00n'
-            b'}\x0c=FAKE\x10\x00\x00\x00n\x00\x00\x00\x05'
-            b'\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x80\x01\x00\x00\x00'
-            b'\x00afilePK\x05\x06\x00\x00\x00\x00\x01\x00'
-            b'\x01\x003\x00\x00\x003\x00\x00\x00\x00\x00')
+        b'PK\x03\x04\x14\x00\x00\x00\x08\x00n}\x0c=FA'
+        b'KE\x10\x00\x00\x00n\x00\x00\x00\x05\x00\x00\x00af'
+        b'ile\xcbH\xcd\xc9\xc9W(\xcf/\xcaI\xc9\xa0'
+        b'=\x13\x00PK\x01\x02\x14\x03\x14\x00\x00\x00\x08\x00n'
+        b'}\x0c=FAKE\x10\x00\x00\x00n\x00\x00\x00\x05'
+        b'\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x80\x01\x00\x00\x00'
+        b'\x00afilePK\x05\x06\x00\x00\x00\x00\x01\x00'
+        b'\x01\x003\x00\x00\x003\x00\x00\x00\x00\x00')
 
 @requires_bz2
 class Bzip2BadCrcTests(AbstractBadCrcTests, unittest.TestCase):
     compression = zipfile.ZIP_BZIP2
     zip_with_bad_crc = (
-            b'PK\x03\x04\x14\x03\x00\x00\x0c\x00nu\x0c=FA'
-            b'KE8\x00\x00\x00n\x00\x00\x00\x05\x00\x00\x00af'
-            b'ileBZh91AY&SY\xd4\xa8\xca'
-            b'\x7f\x00\x00\x0f\x11\x80@\x00\x06D\x90\x80 \x00 \xa5'
-            b'P\xd9!\x03\x03\x13\x13\x13\x89\xa9\xa9\xc2u5:\x9f'
-            b'\x8b\xb9"\x9c(HjTe?\x80PK\x01\x02\x14'
-            b'\x03\x14\x03\x00\x00\x0c\x00nu\x0c=FAKE8'
-            b'\x00\x00\x00n\x00\x00\x00\x05\x00\x00\x00\x00\x00\x00\x00\x00'
-            b'\x00 \x80\x80\x81\x00\x00\x00\x00afilePK'
-            b'\x05\x06\x00\x00\x00\x00\x01\x00\x01\x003\x00\x00\x00[\x00'
-            b'\x00\x00\x00\x00')
+        b'PK\x03\x04\x14\x03\x00\x00\x0c\x00nu\x0c=FA'
+        b'KE8\x00\x00\x00n\x00\x00\x00\x05\x00\x00\x00af'
+        b'ileBZh91AY&SY\xd4\xa8\xca'
+        b'\x7f\x00\x00\x0f\x11\x80@\x00\x06D\x90\x80 \x00 \xa5'
+        b'P\xd9!\x03\x03\x13\x13\x13\x89\xa9\xa9\xc2u5:\x9f'
+        b'\x8b\xb9"\x9c(HjTe?\x80PK\x01\x02\x14'
+        b'\x03\x14\x03\x00\x00\x0c\x00nu\x0c=FAKE8'
+        b'\x00\x00\x00n\x00\x00\x00\x05\x00\x00\x00\x00\x00\x00\x00\x00'
+        b'\x00 \x80\x80\x81\x00\x00\x00\x00afilePK'
+        b'\x05\x06\x00\x00\x00\x00\x01\x00\x01\x003\x00\x00\x00[\x00'
+        b'\x00\x00\x00\x00')
 
 @requires_lzma
 class LzmaBadCrcTests(AbstractBadCrcTests, unittest.TestCase):
     compression = zipfile.ZIP_LZMA
     zip_with_bad_crc = (
-            b'PK\x03\x04\x14\x03\x00\x00\x0e\x00nu\x0c=FA'
-            b'KE\x1b\x00\x00\x00n\x00\x00\x00\x05\x00\x00\x00af'
-            b'ile\t\x04\x05\x00]\x00\x00\x00\x04\x004\x19I'
-            b'\xee\x8d\xe9\x17\x89:3`\tq!.8\x00PK'
-            b'\x01\x02\x14\x03\x14\x03\x00\x00\x0e\x00nu\x0c=FA'
-            b'KE\x1b\x00\x00\x00n\x00\x00\x00\x05\x00\x00\x00\x00\x00'
-            b'\x00\x00\x00\x00 \x80\x80\x81\x00\x00\x00\x00afil'
-            b'ePK\x05\x06\x00\x00\x00\x00\x01\x00\x01\x003\x00\x00'
-            b'\x00>\x00\x00\x00\x00\x00')
+        b'PK\x03\x04\x14\x03\x00\x00\x0e\x00nu\x0c=FA'
+        b'KE\x1b\x00\x00\x00n\x00\x00\x00\x05\x00\x00\x00af'
+        b'ile\t\x04\x05\x00]\x00\x00\x00\x04\x004\x19I'
+        b'\xee\x8d\xe9\x17\x89:3`\tq!.8\x00PK'
+        b'\x01\x02\x14\x03\x14\x03\x00\x00\x0e\x00nu\x0c=FA'
+        b'KE\x1b\x00\x00\x00n\x00\x00\x00\x05\x00\x00\x00\x00\x00'
+        b'\x00\x00\x00\x00 \x80\x80\x81\x00\x00\x00\x00afil'
+        b'ePK\x05\x06\x00\x00\x00\x00\x01\x00\x01\x003\x00\x00'
+        b'\x00>\x00\x00\x00\x00\x00')
 
 
 class DecryptionTests(unittest.TestCase):
@@ -1291,22 +1313,22 @@
     ZIP file."""
 
     data = (
-    b'PK\x03\x04\x14\x00\x01\x00\x00\x00n\x92i.#y\xef?&\x00\x00\x00\x1a\x00'
-    b'\x00\x00\x08\x00\x00\x00test.txt\xfa\x10\xa0gly|\xfa-\xc5\xc0=\xf9y'
-    b'\x18\xe0\xa8r\xb3Z}Lg\xbc\xae\xf9|\x9b\x19\xe4\x8b\xba\xbb)\x8c\xb0\xdbl'
-    b'PK\x01\x02\x14\x00\x14\x00\x01\x00\x00\x00n\x92i.#y\xef?&\x00\x00\x00'
-    b'\x1a\x00\x00\x00\x08\x00\x00\x00\x00\x00\x00\x00\x01\x00 \x00\xb6\x81'
-    b'\x00\x00\x00\x00test.txtPK\x05\x06\x00\x00\x00\x00\x01\x00\x01\x006\x00'
-    b'\x00\x00L\x00\x00\x00\x00\x00' )
+        b'PK\x03\x04\x14\x00\x01\x00\x00\x00n\x92i.#y\xef?&\x00\x00\x00\x1a\x00'
+        b'\x00\x00\x08\x00\x00\x00test.txt\xfa\x10\xa0gly|\xfa-\xc5\xc0=\xf9y'
+        b'\x18\xe0\xa8r\xb3Z}Lg\xbc\xae\xf9|\x9b\x19\xe4\x8b\xba\xbb)\x8c\xb0\xdbl'
+        b'PK\x01\x02\x14\x00\x14\x00\x01\x00\x00\x00n\x92i.#y\xef?&\x00\x00\x00'
+        b'\x1a\x00\x00\x00\x08\x00\x00\x00\x00\x00\x00\x00\x01\x00 \x00\xb6\x81'
+        b'\x00\x00\x00\x00test.txtPK\x05\x06\x00\x00\x00\x00\x01\x00\x01\x006\x00'
+        b'\x00\x00L\x00\x00\x00\x00\x00' )
     data2 = (
-    b'PK\x03\x04\x14\x00\t\x00\x08\x00\xcf}38xu\xaa\xb2\x14\x00\x00\x00\x00\x02'
-    b'\x00\x00\x04\x00\x15\x00zeroUT\t\x00\x03\xd6\x8b\x92G\xda\x8b\x92GUx\x04'
-    b'\x00\xe8\x03\xe8\x03\xc7<M\xb5a\xceX\xa3Y&\x8b{oE\xd7\x9d\x8c\x98\x02\xc0'
-    b'PK\x07\x08xu\xaa\xb2\x14\x00\x00\x00\x00\x02\x00\x00PK\x01\x02\x17\x03'
-    b'\x14\x00\t\x00\x08\x00\xcf}38xu\xaa\xb2\x14\x00\x00\x00\x00\x02\x00\x00'
-    b'\x04\x00\r\x00\x00\x00\x00\x00\x00\x00\x00\x00\xa4\x81\x00\x00\x00\x00ze'
-    b'roUT\x05\x00\x03\xd6\x8b\x92GUx\x00\x00PK\x05\x06\x00\x00\x00\x00\x01'
-    b'\x00\x01\x00?\x00\x00\x00[\x00\x00\x00\x00\x00' )
+        b'PK\x03\x04\x14\x00\t\x00\x08\x00\xcf}38xu\xaa\xb2\x14\x00\x00\x00\x00\x02'
+        b'\x00\x00\x04\x00\x15\x00zeroUT\t\x00\x03\xd6\x8b\x92G\xda\x8b\x92GUx\x04'
+        b'\x00\xe8\x03\xe8\x03\xc7<M\xb5a\xceX\xa3Y&\x8b{oE\xd7\x9d\x8c\x98\x02\xc0'
+        b'PK\x07\x08xu\xaa\xb2\x14\x00\x00\x00\x00\x02\x00\x00PK\x01\x02\x17\x03'
+        b'\x14\x00\t\x00\x08\x00\xcf}38xu\xaa\xb2\x14\x00\x00\x00\x00\x02\x00\x00'
+        b'\x04\x00\r\x00\x00\x00\x00\x00\x00\x00\x00\x00\xa4\x81\x00\x00\x00\x00ze'
+        b'roUT\x05\x00\x03\xd6\x8b\x92GUx\x00\x00PK\x05\x06\x00\x00\x00\x00\x01'
+        b'\x00\x01\x00?\x00\x00\x00[\x00\x00\x00\x00\x00' )
 
     plain = b'zipfile.py encryption test'
     plain2 = b'\x00'*512
diff --git a/Lib/zipfile.py b/Lib/zipfile.py
index ff58347..b3554fb 100644
--- a/Lib/zipfile.py
+++ b/Lib/zipfile.py
@@ -211,8 +211,8 @@
     if len(data) != sizeEndCentDir64:
         return endrec
     sig, sz, create_version, read_version, disk_num, disk_dir, \
-            dircount, dircount2, dirsize, diroffset = \
-            struct.unpack(structEndArchive64, data)
+        dircount, dircount2, dirsize, diroffset = \
+        struct.unpack(structEndArchive64, data)
     if sig != stringEndArchive64:
         return endrec
 
@@ -292,26 +292,26 @@
     """Class with attributes describing each file in the ZIP archive."""
 
     __slots__ = (
-            'orig_filename',
-            'filename',
-            'date_time',
-            'compress_type',
-            'comment',
-            'extra',
-            'create_system',
-            'create_version',
-            'extract_version',
-            'reserved',
-            'flag_bits',
-            'volume',
-            'internal_attr',
-            'external_attr',
-            'header_offset',
-            'CRC',
-            'compress_size',
-            'file_size',
-            '_raw_time',
-        )
+        'orig_filename',
+        'filename',
+        'date_time',
+        'compress_type',
+        'comment',
+        'extra',
+        'create_system',
+        'create_version',
+        'extract_version',
+        'reserved',
+        'flag_bits',
+        'volume',
+        'internal_attr',
+        'external_attr',
+        'header_offset',
+        'CRC',
+        'compress_size',
+        'file_size',
+        '_raw_time',
+    )
 
     def __init__(self, filename="NoName", date_time=(1980,1,1,0,0,0)):
         self.orig_filename = filename   # Original file name in archive
@@ -376,7 +376,7 @@
         if zip64:
             fmt = '<HHQQ'
             extra = extra + struct.pack(fmt,
-                    1, struct.calcsize(fmt)-4, file_size, compress_size)
+                                        1, struct.calcsize(fmt)-4, file_size, compress_size)
         if file_size > ZIP64_LIMIT or compress_size > ZIP64_LIMIT:
             if not zip64:
                 raise LargeZipFile("Filesize would require ZIP64 extensions")
@@ -395,10 +395,10 @@
         self.create_version = max(min_version, self.create_version)
         filename, flag_bits = self._encodeFilenameFlags()
         header = struct.pack(structFileHeader, stringFileHeader,
-                 self.extract_version, self.reserved, flag_bits,
-                 self.compress_type, dostime, dosdate, CRC,
-                 compress_size, file_size,
-                 len(filename), len(extra))
+                             self.extract_version, self.reserved, flag_bits,
+                             self.compress_type, dostime, dosdate, CRC,
+                             compress_size, file_size,
+                             len(filename), len(extra))
         return header + filename + extra
 
     def _encodeFilenameFlags(self):
@@ -511,7 +511,7 @@
     def _init(self):
         props = lzma._encode_filter_properties({'id': lzma.FILTER_LZMA1})
         self._comp = lzma.LZMACompressor(lzma.FORMAT_RAW, filters=[
-                lzma._decode_filter_properties(lzma.FILTER_LZMA1, props)
+            lzma._decode_filter_properties(lzma.FILTER_LZMA1, props)
         ])
         return struct.pack('<BBH', 9, 4, len(props)) + props
 
@@ -543,8 +543,8 @@
                 return b''
 
             self._decomp = lzma.LZMADecompressor(lzma.FORMAT_RAW, filters=[
-                    lzma._decode_filter_properties(lzma.FILTER_LZMA1,
-                            self._unconsumed[4:4 + psize])
+                lzma._decode_filter_properties(lzma.FILTER_LZMA1,
+                                               self._unconsumed[4:4 + psize])
             ])
             data = self._unconsumed[4 + psize:]
             del self._unconsumed
@@ -580,15 +580,15 @@
     elif compression == ZIP_DEFLATED:
         if not zlib:
             raise RuntimeError(
-                    "Compression requires the (missing) zlib module")
+                "Compression requires the (missing) zlib module")
     elif compression == ZIP_BZIP2:
         if not bz2:
             raise RuntimeError(
-                    "Compression requires the (missing) bz2 module")
+                "Compression requires the (missing) bz2 module")
     elif compression == ZIP_LZMA:
         if not lzma:
             raise RuntimeError(
-                    "Compression requires the (missing) lzma module")
+                "Compression requires the (missing) lzma module")
     else:
         raise RuntimeError("That compression method is not supported")
 
@@ -596,7 +596,7 @@
 def _get_compressor(compress_type):
     if compress_type == ZIP_DEFLATED:
         return zlib.compressobj(zlib.Z_DEFAULT_COMPRESSION,
-             zlib.DEFLATED, -15)
+                                zlib.DEFLATED, -15)
     elif compress_type == ZIP_BZIP2:
         return bz2.BZ2Compressor()
     elif compress_type == ZIP_LZMA:
@@ -836,8 +836,8 @@
             n = max(n, self.MIN_READ_SIZE)
             data = self._decompressor.decompress(data, n)
             self._eof = (self._decompressor.eof or
-                    self._compress_left <= 0 and
-                    not self._decompressor.unconsumed_tail)
+                         self._compress_left <= 0 and
+                         not self._decompressor.unconsumed_tail)
             if self._eof:
                 data += self._decompressor.flush()
         else:
@@ -1016,8 +1016,8 @@
             x.comment = fp.read(centdir[_CD_COMMENT_LENGTH])
             x.header_offset = centdir[_CD_LOCAL_HEADER_OFFSET]
             (x.create_version, x.create_system, x.extract_version, x.reserved,
-                x.flag_bits, x.compress_type, t, d,
-                x.CRC, x.compress_size, x.file_size) = centdir[1:12]
+             x.flag_bits, x.compress_type, t, d,
+             x.CRC, x.compress_size, x.file_size) = centdir[1:12]
             if x.extract_version > MAX_EXTRACT_VERSION:
                 raise NotImplementedError("zip file version %.1f" %
                                           (x.extract_version / 10))
@@ -1025,7 +1025,7 @@
             # Convert date/time code to (year, month, day, hour, min, sec)
             x._raw_time = t
             x.date_time = ( (d>>9)+1980, (d>>5)&0xF, d&0x1F,
-                                     t>>11, (t>>5)&0x3F, (t&0x1F) * 2 )
+                            t>>11, (t>>5)&0x3F, (t&0x1F) * 2 )
 
             x._decodeExtra()
             x.header_offset = x.header_offset + concat
@@ -1103,7 +1103,7 @@
         if len(comment) >= ZIP_MAX_COMMENT:
             if self.debug:
                 print('Archive comment is too long; truncating to %d bytes'
-                        % ZIP_MAX_COMMENT)
+                      % ZIP_MAX_COMMENT)
             comment = comment[:ZIP_MAX_COMMENT]
         self._comment = comment
         self._didModify = True
@@ -1121,7 +1121,7 @@
             raise TypeError("pwd: expected bytes, got %s" % type(pwd))
         if not self.fp:
             raise RuntimeError(
-                  "Attempt to read ZIP archive that was already closed")
+                "Attempt to read ZIP archive that was already closed")
 
         # Only open a new file for instances where we were not
         # given a file object in the constructor
@@ -1294,7 +1294,7 @@
             raise RuntimeError('write() requires mode "w" or "a"')
         if not self.fp:
             raise RuntimeError(
-                  "Attempt to write ZIP archive that was already closed")
+                "Attempt to write ZIP archive that was already closed")
         _check_compression(zinfo.compress_type)
         if zinfo.file_size > ZIP64_LIMIT:
             if not self._allowZip64:
@@ -1302,14 +1302,14 @@
         if zinfo.header_offset > ZIP64_LIMIT:
             if not self._allowZip64:
                 raise LargeZipFile(
-                      "Zipfile size would require ZIP64 extensions")
+                    "Zipfile size would require ZIP64 extensions")
 
     def write(self, filename, arcname=None, compress_type=None):
         """Put the bytes from filename into the archive under the name
         arcname."""
         if not self.fp:
             raise RuntimeError(
-                  "Attempt to write to ZIP archive that was already closed")
+                "Attempt to write to ZIP archive that was already closed")
 
         st = os.stat(filename)
         isdir = stat.S_ISDIR(st.st_mode)
@@ -1356,7 +1356,7 @@
             zinfo.compress_size = compress_size = 0
             # Compressed size can be larger than uncompressed size
             zip64 = self._allowZip64 and \
-                    zinfo.file_size * 1.05 > ZIP64_LIMIT
+                zinfo.file_size * 1.05 > ZIP64_LIMIT
             self.fp.write(zinfo.FileHeader(zip64))
             file_size = 0
             while 1:
@@ -1410,7 +1410,7 @@
 
         if not self.fp:
             raise RuntimeError(
-                  "Attempt to write to ZIP archive that was already closed")
+                "Attempt to write to ZIP archive that was already closed")
 
         zinfo.file_size = len(data)            # Uncompressed size
         zinfo.header_offset = self.fp.tell()    # Start of header data
@@ -1430,7 +1430,7 @@
         else:
             zinfo.compress_size = zinfo.file_size
         zip64 = zinfo.file_size > ZIP64_LIMIT or \
-                zinfo.compress_size > ZIP64_LIMIT
+            zinfo.compress_size > ZIP64_LIMIT
         if zip64 and not self._allowZip64:
             raise LargeZipFile("Filesize would require ZIP64 extensions")
         self.fp.write(zinfo.FileHeader(zip64))
@@ -1439,7 +1439,7 @@
             # Write CRC and file sizes after the file data
             fmt = '<LQQ' if zip64 else '<LLL'
             self.fp.write(struct.pack(fmt, zinfo.CRC, zinfo.compress_size,
-                  zinfo.file_size))
+                                      zinfo.file_size))
         self.fp.flush()
         self.filelist.append(zinfo)
         self.NameToInfo[zinfo.filename] = zinfo
@@ -1465,7 +1465,7 @@
                     dostime = dt[3] << 11 | dt[4] << 5 | (dt[5] // 2)
                     extra = []
                     if zinfo.file_size > ZIP64_LIMIT \
-                            or zinfo.compress_size > ZIP64_LIMIT:
+                       or zinfo.compress_size > ZIP64_LIMIT:
                         extra.append(zinfo.file_size)
                         extra.append(zinfo.compress_size)
                         file_size = 0xffffffff
@@ -1485,8 +1485,8 @@
                     if extra:
                         # Append a ZIP64 field to the extra's
                         extra_data = struct.pack(
-                                '<HH' + 'Q'*len(extra),
-                                1, 8*len(extra), *extra) + extra_data
+                            '<HH' + 'Q'*len(extra),
+                            1, 8*len(extra), *extra) + extra_data
 
                         min_version = ZIP64_VERSION
 
@@ -1500,21 +1500,21 @@
                     try:
                         filename, flag_bits = zinfo._encodeFilenameFlags()
                         centdir = struct.pack(structCentralDir,
-                            stringCentralDir, create_version,
-                            zinfo.create_system, extract_version, zinfo.reserved,
-                            flag_bits, zinfo.compress_type, dostime, dosdate,
-                            zinfo.CRC, compress_size, file_size,
-                            len(filename), len(extra_data), len(zinfo.comment),
-                            0, zinfo.internal_attr, zinfo.external_attr,
-                            header_offset)
+                                              stringCentralDir, create_version,
+                                              zinfo.create_system, extract_version, zinfo.reserved,
+                                              flag_bits, zinfo.compress_type, dostime, dosdate,
+                                              zinfo.CRC, compress_size, file_size,
+                                              len(filename), len(extra_data), len(zinfo.comment),
+                                              0, zinfo.internal_attr, zinfo.external_attr,
+                                              header_offset)
                     except DeprecationWarning:
                         print((structCentralDir, stringCentralDir, create_version,
-                            zinfo.create_system, extract_version, zinfo.reserved,
-                            zinfo.flag_bits, zinfo.compress_type, dostime, dosdate,
-                            zinfo.CRC, compress_size, file_size,
-                            len(zinfo.filename), len(extra_data), len(zinfo.comment),
-                            0, zinfo.internal_attr, zinfo.external_attr,
-                            header_offset), file=sys.stderr)
+                               zinfo.create_system, extract_version, zinfo.reserved,
+                               zinfo.flag_bits, zinfo.compress_type, dostime, dosdate,
+                               zinfo.CRC, compress_size, file_size,
+                               len(zinfo.filename), len(extra_data), len(zinfo.comment),
+                               0, zinfo.internal_attr, zinfo.external_attr,
+                               header_offset), file=sys.stderr)
                         raise
                     self.fp.write(centdir)
                     self.fp.write(filename)
@@ -1531,22 +1531,22 @@
                     centDirSize > ZIP64_LIMIT):
                     # Need to write the ZIP64 end-of-archive records
                     zip64endrec = struct.pack(
-                            structEndArchive64, stringEndArchive64,
-                            44, 45, 45, 0, 0, centDirCount, centDirCount,
-                            centDirSize, centDirOffset)
+                        structEndArchive64, stringEndArchive64,
+                        44, 45, 45, 0, 0, centDirCount, centDirCount,
+                        centDirSize, centDirOffset)
                     self.fp.write(zip64endrec)
 
                     zip64locrec = struct.pack(
-                            structEndArchive64Locator,
-                            stringEndArchive64Locator, 0, pos2, 1)
+                        structEndArchive64Locator,
+                        stringEndArchive64Locator, 0, pos2, 1)
                     self.fp.write(zip64locrec)
                     centDirCount = min(centDirCount, 0xFFFF)
                     centDirSize = min(centDirSize, 0xFFFFFFFF)
                     centDirOffset = min(centDirOffset, 0xFFFFFFFF)
 
                 endrec = struct.pack(structEndArchive, stringEndArchive,
-                                    0, 0, centDirCount, centDirCount,
-                                    centDirSize, centDirOffset, len(self._comment))
+                                     0, 0, centDirCount, centDirCount,
+                                     centDirSize, centDirOffset, len(self._comment))
                 self.fp.write(endrec)
                 self.fp.write(self._comment)
                 self.fp.flush()
@@ -1566,7 +1566,7 @@
                          allowZip64=allowZip64)
         self._optimize = optimize
 
-    def writepy(self, pathname, basename=""):
+    def writepy(self, pathname, basename="", filterfunc=None):
         """Add all files from "pathname" to the ZIP archive.
 
         If pathname is a package directory, search the directory and
@@ -1577,7 +1577,13 @@
         archive.  Added modules are always module.pyo or module.pyc.
         This method will compile the module.py into module.pyc if
         necessary.
+        If filterfunc(pathname) is given, it is called with every argument.
+        When it is False, the file or directory is skipped.
         """
+        if filterfunc and not filterfunc(pathname):
+            if self.debug:
+                print('pathname "%s" skipped by filterfunc' % pathname)
+            return
         dir, name = os.path.split(pathname)
         if os.path.isdir(pathname):
             initname = os.path.join(pathname, "__init__.py")
@@ -1602,10 +1608,11 @@
                     if os.path.isdir(path):
                         if os.path.isfile(os.path.join(path, "__init__.py")):
                             # This is a package directory, add it
-                            self.writepy(path, basename)  # Recursive call
+                            self.writepy(path, basename,
+                                         filterfunc=filterfunc)  # Recursive call
                     elif ext == ".py":
                         fname, arcname = self._get_codename(path[0:-3],
-                                         basename)
+                                                            basename)
                         if self.debug:
                             print("Adding", arcname)
                         self.write(fname, arcname)
@@ -1618,14 +1625,14 @@
                     root, ext = os.path.splitext(filename)
                     if ext == ".py":
                         fname, arcname = self._get_codename(path[0:-3],
-                                         basename)
+                                                            basename)
                         if self.debug:
                             print("Adding", arcname)
                         self.write(fname, arcname)
         else:
             if pathname[-3:] != ".py":
                 raise RuntimeError(
-                      'Files added with writepy() must end with ".py"')
+                    'Files added with writepy() must end with ".py"')
             fname, arcname = self._get_codename(pathname[0:-3], basename)
             if self.debug:
                 print("Adding file", arcname)
@@ -1764,7 +1771,7 @@
             elif os.path.isdir(path):
                 for nm in os.listdir(path):
                     addToZip(zf,
-                            os.path.join(path, nm), os.path.join(zippath, nm))
+                             os.path.join(path, nm), os.path.join(zippath, nm))
             # else: ignore
 
         with ZipFile(args[1], 'w', allowZip64=True) as zf: