code: def get_device_model(self, cat, sub_cat, key=''):
          
          if cat + ':' + sub_cat in self.device_models:
              return self.device_models[cat + ':' + sub_cat]
          else:
              for i_key, i_val in self.device_models.items():
                  if 'key' in i_val:
                      if i_val['key'] == key:
                          return i_val
              return False
docs: Return the model name given cat/subcat or product key