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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 post_public_key(self, path, data, is_json=True):
        '''Make a post request using a public key.'''
        post_data = {
            'public_key': self.public_key
        }
        post_data.update(data)
        return self._post(path, post_data, is_json)