code: def find(self, rtype, key, val):
          
  
          model = rtype_to_model(rtype)
          param = {'key': key, 'val': val}
          query = """
                  SELECT {cols} FROM {table}
                  WHERE {key} = %(val)s;
                  """
  
          query = query.format(
              cols=self.field_cols(model),
              key=key,
              table=rtype,
          )
  
          signals.pre_find.send(model.__class__, model=model)
  
          result = self.query(query, param=param)
          if result:
              result = model(result[0])
              signals.post_find.send(model.__class__, model=result)
  
          return result or None
docs: Given a resource type & a single key/val find the model
  
          A single instantiated model object found by the key/val
          will be returned if a match is found in the database.
          If no record can be found then return None.
  
          WARN: This isn't for complex queries! Use search() instead.
  
          :return: model or None