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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 save_configuration(self):
 """ Save the PyPI access configuration. You must have set ``username`` and ``password`` attributes before calling this method. Again, distutils is used to do the actual work. """

        self.check_credentials()
        # get distutils to do the work
        c = self._get_pypirc_command()
        c._store_pypirc(self.username, self.password)