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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(self):
 """ Get the Content-Type header from the response. Strip the ";charset=xxxxx" portion if necessary. If we can't find it, use the predefined format. """

        if ';' in self.headers.get('Content-Type', ''):
            return self.headers['Content-Type'].split(';')[0]
        return self.headers.get('Content-Type', self.static_format)