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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 guess_mimetype(filename):
 """Map extra mimetype with the encoding provided. :returns: The extra mimetype. """

    m, encoding = mimetypes.guess_type(filename)
    if encoding:
        m = ENCODING_MIMETYPES.get(encoding, None)
    return m or 'application/octet-stream'