code: def assets(self, asset_type=None):
          
          if not self.can_update():
              self._tcex.handle_error(910, [self.type])
  
          if not asset_type:
              return self.tc_requests.adversary_assets(
                  self.api_type, self.api_sub_type, self.unique_id
              )
          if asset_type == 'PHONE':
              return self.tc_requests.adversary_phone_assets(
                  self.api_type, self.api_sub_type, self.unique_id
              )
          if asset_type == 'HANDLER':
              return self.tc_requests.adversary_handle_assets(
                  self.api_type, self.api_sub_type, self.unique_id
              )
          if asset_type == 'URL':
              return self.tc_requests.adversary_url_assets(
                  self.api_type, self.api_sub_type, self.unique_id
              )
  
          self._tcex.handle_error(
              925, ['asset_type', 'assets', 'asset_type', 'asset_type', asset_type]
          )
          return None
docs: Retrieves all of the assets of a given asset_type
  
          Args:
              asset_type: (str) Either None, PHONE, HANDLER, or URL
  
          Returns: