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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 _obtain_api_token(self, username, password):
 """Use username and password to obtain and return an API token."""

        data = self._request("POST", "auth/apitoken",
                             {"username": username, "password": password},
                             reestablish_session=False)
        return data["api_token"]