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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 get_user(self, username):
 """Retrieve information about a user Returns: dict: User information None: If no user or failure occurred """


        response = self._get(self.rest_url + "/user",
                             params={"username": username,
                                     "expand": "attributes"})

        if not response.ok:
            return None

        return response.json()