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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 register(self, metadata):
 """ Register a distribution on PyPI, using the provided metadata. :param metadata: A :class:`Metadata` instance defining at least a name and version number for the distribution to be registered. :return: The HTTP response received from PyPI upon submission of the request. """

        self.check_credentials()
        metadata.validate()
        d = metadata.todict()
        d[':action'] = 'verify'
        request = self.encode_request(d.items(), [])
        response = self.send_request(request)
        d[':action'] = 'submit'
        request = self.encode_request(d.items(), [])
        return self.send_request(request)