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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 mimetype_from_path(path):
 """ Return a mimetype from the file extension. :param string path: the file path :rtype: string """

    extension = file_extension(path)
    if extension is not None:
        extension = extension.lower()
        if extension in gc.MIMETYPE_MAP:
            return gc.MIMETYPE_MAP[extension]
    return None