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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 load_mmd():
 """Loads libMultiMarkdown for usage"""

    global _MMD_LIB
    global _LIB_LOCATION
    try:
        lib_file = 'libMultiMarkdown' + SHLIB_EXT[platform.system()]
        _LIB_LOCATION = os.path.abspath(os.path.join(DEFAULT_LIBRARY_DIR, lib_file))

        if not os.path.isfile(_LIB_LOCATION):
            _LIB_LOCATION = ctypes.util.find_library('MultiMarkdown')

        _MMD_LIB = ctypes.cdll.LoadLibrary(_LIB_LOCATION)
    except:
        _MMD_LIB = None