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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 encoding(self):
 """the character encoding of the request, usually only set in POST type requests"""

        encoding = None
        ct = self.get_header('content-type')
        if ct:
            ah = AcceptHeader(ct)
            if ah.media_types:
                encoding = ah.media_types[0][2].get("charset", None)

        return encoding