diff --git a/create_timing_table.py b/create_timing_table.py
index 48cd1ff..1c31b98 100755
--- a/create_timing_table.py
+++ b/create_timing_table.py
@@ -39,5 +39,6 @@
           (bitsize, dur_per_call, iterations, duration))
 
 
-for bitsize in (128, 256, 384, 512, 1024, 2048, 3072, 4096):
-    run_speed_test(bitsize)
+if __name__ == '__main__':
+    for bitsize in (128, 256, 384, 512, 1024, 2048, 3072, 4096):
+        run_speed_test(bitsize)
diff --git a/rsa/_version133.py b/rsa/_version133.py
index f059a18..b30b695 100644
--- a/rsa/_version133.py
+++ b/rsa/_version133.py
@@ -67,12 +67,6 @@
 
 def bytes2int(bytes):
     """Converts a list of bytes or a string to an integer
-
-    >>> (128*256 + 64)*256 + + 15
-    8405007
-    >>> l = [128, 64, 15]
-    >>> bytes2int(l)
-    8405007
     """
 
     if not (type(bytes) is types.ListType or type(bytes) is types.StringType):
@@ -89,9 +83,6 @@
 
 def int2bytes(number):
     """Converts a number to a string of bytes
-    
-    >>> bytes2int(int2bytes(123456789))
-    123456789
     """
 
     if not (type(number) is types.LongType or type(number) is types.IntType):
@@ -208,11 +199,6 @@
 
 def is_prime(number):
     """Returns True if the number is prime, and False otherwise.
-
-    >>> is_prime(42)
-    0
-    >>> is_prime(41)
-    1
     """
 
     """
@@ -232,14 +218,6 @@
 def getprime(nbits):
     """Returns a prime number of max. 'math.ceil(nbits/8)*8' bits. In
     other words: nbits is rounded up to whole bytes.
-
-    >>> p = getprime(8)
-    >>> is_prime(p-1)
-    0
-    >>> is_prime(p)
-    1
-    >>> is_prime(p+1)
-    0
     """
 
     nbytes = int(math.ceil(nbits/8.))
@@ -260,11 +238,6 @@
 def are_relatively_prime(a, b):
     """Returns True if a and b are relatively prime, and False if they
     are not.
-
-    >>> are_relatively_prime(2, 3)
-    1
-    >>> are_relatively_prime(2, 4)
-    0
     """
 
     d = gcd(a, b)
diff --git a/rsa/_version200.py b/rsa/_version200.py
index eba0d27..717b6ac 100644
--- a/rsa/_version200.py
+++ b/rsa/_version200.py
@@ -60,12 +60,6 @@
 
 def bytes2int(bytes):
     r"""Converts a list of bytes or a string to an integer
-
-    >>> (((128 * 256) + 64) * 256) + 15
-    8405007
-    >>> l = [128, 64, 15]
-    >>> bytes2int(l)              #same as bytes2int('\x80@\x0f')
-    8405007
     """
 
     if not (type(bytes) is types.ListType or type(bytes) is types.StringType):
@@ -99,9 +93,6 @@
 def to64(number):
     """Converts a number in the range of 0 to 63 into base 64 digit
     character in the range of '0'-'9', 'A'-'Z', 'a'-'z','-','_'.
-    
-    >>> to64(10)
-    'A'
     """
 
     if not (type(number) is types.LongType or type(number) is types.IntType):
@@ -128,9 +119,6 @@
 def from64(number):
     """Converts an ordinal character value in the range of
     0-9,A-Z,a-z,-,_ to a number in the range of 0-63.
-    
-    >>> from64(49)
-    1
     """
 
     if not (type(number) is types.LongType or type(number) is types.IntType):
@@ -157,9 +145,6 @@
 def int2str64(number):
     """Converts a number to a string of base64 encoded characters in
     the range of '0'-'9','A'-'Z,'a'-'z','-','_'.
-    
-    >>> int2str64(123456789)
-    '7MyqL'
     """
 
     if not (type(number) is types.LongType or type(number) is types.IntType):
@@ -177,9 +162,6 @@
 def str642int(string):
     """Converts a base64 encoded string into an integer.
     The chars of this string in in the range '0'-'9','A'-'Z','a'-'z','-','_'
-    
-    >>> str642int('7MyqL')
-    123456789
     """
 
     if not (type(string) is types.ListType or type(string) is types.StringType):
@@ -270,11 +252,6 @@
 
 def is_prime(number):
     """Returns True if the number is prime, and False otherwise.
-
-    >>> is_prime(42)
-    0
-    >>> is_prime(41)
-    1
     """
 
     if randomized_primality_testing(number, 6):
@@ -288,14 +265,6 @@
 def getprime(nbits):
     """Returns a prime number of max. 'math.ceil(nbits/8)*8' bits. In
     other words: nbits is rounded up to whole bytes.
-
-    >>> p = getprime(8)
-    >>> is_prime(p-1)
-    0
-    >>> is_prime(p)
-    1
-    >>> is_prime(p+1)
-    0
     """
 
     while True:
diff --git a/rsa/pkcs1.py b/rsa/pkcs1.py
index fdbbb8b..7d6814c 100644
--- a/rsa/pkcs1.py
+++ b/rsa/pkcs1.py
@@ -69,13 +69,13 @@
 
     :return: 00 02 RANDOM_DATA 00 MESSAGE
 
-    >>> block = _pad_for_encryption('hello', 16)
+    >>> block = _pad_for_encryption(b'hello', 16)
     >>> len(block)
     16
     >>> block[0:2]
-    '\x00\x02'
+    b'\x00\x02'
     >>> block[-6:]
-    '\x00hello'
+    b'\x00hello'
 
     """
 
@@ -117,15 +117,15 @@
 
     :return: 00 01 PADDING 00 MESSAGE
 
-    >>> block = _pad_for_signing('hello', 16)
+    >>> block = _pad_for_signing(b'hello', 16)
     >>> len(block)
     16
     >>> block[0:2]
-    '\x00\x01'
+    b'\x00\x01'
     >>> block[-6:]
-    '\x00hello'
+    b'\x00hello'
     >>> block[2:-6]
-    '\xff\xff\xff\xff\xff\xff\xff\xff'
+    b'\xff\xff\xff\xff\xff\xff\xff\xff'
 
     """
 
@@ -156,7 +156,7 @@
 
     >>> from rsa import key, common
     >>> (pub_key, priv_key) = key.newkeys(256)
-    >>> message = 'hello'
+    >>> message = b'hello'
     >>> crypto = encrypt(message, pub_key)
 
     The crypto text should be just as long as the public key 'n' component:
@@ -195,15 +195,15 @@
 
     It works with strings:
 
-    >>> crypto = encrypt('hello', pub_key)
+    >>> crypto = encrypt(b'hello', pub_key)
     >>> decrypt(crypto, priv_key)
-    'hello'
+    b'hello'
 
     And with binary data:
 
-    >>> crypto = encrypt('\x00\x00\x00\x00\x01', pub_key)
+    >>> crypto = encrypt(b'\x00\x00\x00\x00\x01', pub_key)
     >>> decrypt(crypto, priv_key)
-    '\x00\x00\x00\x00\x01'
+    b'\x00\x00\x00\x00\x01'
 
     Altering the encrypted information will *likely* cause a
     :py:class:`rsa.pkcs1.DecryptionError`. If you want to be *sure*, use
@@ -218,12 +218,12 @@
         It's only a tiny bit of information, but every bit makes cracking the
         keys easier.
 
-    >>> crypto = encrypt('hello', pub_key)
-    >>> crypto = crypto[0:5] + 'X' + crypto[6:] # change a byte
+    >>> crypto = encrypt(b'hello', pub_key)
+    >>> crypto = crypto[0:5] + b'X' + crypto[6:] # change a byte
     >>> decrypt(crypto, priv_key)
     Traceback (most recent call last):
     ...
-    DecryptionError: Decryption failed
+    rsa.pkcs1.DecryptionError: Decryption failed
 
     """
 
diff --git a/rsa/transform.py b/rsa/transform.py
index 889b3f2..758dea4 100644
--- a/rsa/transform.py
+++ b/rsa/transform.py
@@ -44,7 +44,7 @@
 
     >>> (((128 * 256) + 64) * 256) + 15
     8405007
-    >>> bytes2int('\x80@\x0f')
+    >>> bytes2int(b'\x80@\x0f')
     8405007
 
     """
@@ -58,12 +58,12 @@
     Usage::
 
         >>> _int2bytes(123456789)
-        '\x07[\xcd\x15'
+        b'\x07[\xcd\x15'
         >>> bytes2int(_int2bytes(123456789))
         123456789
 
         >>> _int2bytes(123456789, 6)
-        '\x00\x00\x07[\xcd\x15'
+        b'\x00\x00\x07[\xcd\x15'
         >>> bytes2int(_int2bytes(123456789, 128))
         123456789
 
diff --git a/setup.py b/setup.py
index d46945b..428b14c 100755
--- a/setup.py
+++ b/setup.py
@@ -16,39 +16,40 @@
 
 from setuptools import setup
 
-setup(name='rsa',
-      version='3.3',
-      description='Pure-Python RSA implementation',
-      author='Sybren A. Stuvel',
-      author_email='sybren@stuvel.eu',
-      maintainer='Sybren A. Stuvel',
-      maintainer_email='sybren@stuvel.eu',
-      url='https://stuvel.eu/rsa',
-      packages=['rsa'],
-      license='ASL 2',
-      classifiers=[
-          'Development Status :: 5 - Production/Stable',
-          'Intended Audience :: Developers',
-          'Intended Audience :: Education',
-          'Intended Audience :: Information Technology',
-          'License :: OSI Approved :: Apache Software License',
-          'Operating System :: OS Independent',
-          'Programming Language :: Python',
-          'Programming Language :: Python :: 3',
-          'Topic :: Security :: Cryptography',
-      ],
-      install_requires=[
-          'pyasn1 >= 0.1.3',
-      ],
-      entry_points={'console_scripts': [
-          'pyrsa-priv2pub = rsa.util:private_to_public',
-          'pyrsa-keygen = rsa.cli:keygen',
-          'pyrsa-encrypt = rsa.cli:encrypt',
-          'pyrsa-decrypt = rsa.cli:decrypt',
-          'pyrsa-sign = rsa.cli:sign',
-          'pyrsa-verify = rsa.cli:verify',
-          'pyrsa-encrypt-bigfile = rsa.cli:encrypt_bigfile',
-          'pyrsa-decrypt-bigfile = rsa.cli:decrypt_bigfile',
-      ]},
+if __name__ == '__main__':
+    setup(name='rsa',
+          version='3.3',
+          description='Pure-Python RSA implementation',
+          author='Sybren A. Stuvel',
+          author_email='sybren@stuvel.eu',
+          maintainer='Sybren A. Stuvel',
+          maintainer_email='sybren@stuvel.eu',
+          url='https://stuvel.eu/rsa',
+          packages=['rsa'],
+          license='ASL 2',
+          classifiers=[
+              'Development Status :: 5 - Production/Stable',
+              'Intended Audience :: Developers',
+              'Intended Audience :: Education',
+              'Intended Audience :: Information Technology',
+              'License :: OSI Approved :: Apache Software License',
+              'Operating System :: OS Independent',
+              'Programming Language :: Python',
+              'Programming Language :: Python :: 3',
+              'Topic :: Security :: Cryptography',
+          ],
+          install_requires=[
+              'pyasn1 >= 0.1.3',
+          ],
+          entry_points={'console_scripts': [
+              'pyrsa-priv2pub = rsa.util:private_to_public',
+              'pyrsa-keygen = rsa.cli:keygen',
+              'pyrsa-encrypt = rsa.cli:encrypt',
+              'pyrsa-decrypt = rsa.cli:decrypt',
+              'pyrsa-sign = rsa.cli:sign',
+              'pyrsa-verify = rsa.cli:verify',
+              'pyrsa-encrypt-bigfile = rsa.cli:encrypt_bigfile',
+              'pyrsa-decrypt-bigfile = rsa.cli:decrypt_bigfile',
+          ]},
 
-      )
+          )
diff --git a/tox.ini b/tox.ini
index 5932192..f59d647 100644
--- a/tox.ini
+++ b/tox.ini
@@ -3,7 +3,6 @@
 
 [pytest]
 addopts = -v --cov rsa --cov-report term-missing
-# --doctest-modules
 
 [testenv]
 setenv =
@@ -14,3 +13,6 @@
      PyTest
      pytest-xdist
      pytest-cov
+
+[testenv:py35]
+commands=py.test --doctest-modules []