code: def get(self, username, width=None, height=None):
          
          url = "/users/{username}".format(username=username)
          params = {
              "w": width,
              "h": height
          }
          result = self._get(url, params=params)
          return UserModel.parse(result)
docs: 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.