capybara/virtualenv/lib/python2.7/site-packages/pip/utils/__init__.py
def backup_dir(dir, ext='.bak'):
    """Figure out the name of a directory to back up the given dir to
    (adding .bak, .bak2, etc)"""
    n = 1
    extension = ext
    while os.path.exists(dir + extension):
        n += 1
        extension = ext + str(n)
    return dir + extension
def backup_dir(dir, ext='.bak'):
    """Figure out the name of a directory to back up the given dir to
    (adding .bak, .bak2, etc)"""
    n = 1
    extension = ext
    while os.path.exists(dir + extension):
        n += 1
        extension = ext + str(n)
    return dir + extension
def backup_dir ( dir , ext = '.bak' ) : n = 1 extension = ext while os . path . exists ( dir + extension ) : n += 1 extension = ext + str ( n ) return dir + extension
Figure out the name of a directory to back up the given dir to
    (adding .bak, .bak2, etc)
Figure out the name of a directory to back up the given dir to ( adding . bak . bak2 etc )