Create lldbsuite.support package with `seven` file.

This file will be useful for filling in the gaps where `six` is
missing some things we need.

llvm-svn: 251847
diff --git a/lldb/packages/Python/lldbsuite/support/seven.py b/lldb/packages/Python/lldbsuite/support/seven.py
new file mode 100644
index 0000000..1aab61f
--- /dev/null
+++ b/lldb/packages/Python/lldbsuite/support/seven.py
@@ -0,0 +1,17 @@
+import six
+
+if six.PY2:
+    import commands
+    get_command_output = commands.getoutput
+    get_command_status_output = commands.getstatusoutput
+
+else:
+    def get_command_status_output(command):
+        try:
+            import subprocess
+            return (0, subprocess.check_output(command, shell=True))
+        except subprocess.CalledProcessError as e:
+            return (e.returncode, e.output)
+
+    def get_command_output(command):
+        return get_command_status_output(command)[1]