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Solve the following problem using Python, implementing the functions described below, one line at a time
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Description:
 def get_os_filename (path):
 """Return filesystem path for given URL path."""

    if os.name == 'nt':
        path = prepare_urlpath_for_nt(path)
    res = urllib.url2pathname(fileutil.pathencode(path))
    if os.name == 'nt' and res.endswith(':') and len(res) == 2:
        # Work around http://bugs.python.org/issue11474
        res += os.sep
    return res