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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(self, username, width=None, height=None):
 """ Retrieve public details on a given user. Note: Supplying the optional w or h parameters will result in the 'custom' photo URL being added to the 'profile_image' object: :param username [string]: The user’s username. Required. :param width [integer]: Profile image width in pixels. :param height [integer]: Profile image height in pixels. :return: [User]: The Unsplash User. """

        url = "/users/{username}".format(username=username)
        params = {
            "w": width,
            "h": height
        }
        result = self._get(url, params=params)
        return UserModel.parse(result)