code: def _may_override(self, implem, other):
          
          if isinstance(other, ImplementationProperty):
              # Overriding another custom implementation for the same transition
              # and field
              return (other.transition == implem.transition and other.field_name == self.state_field)
  
          elif isinstance(other, TransitionWrapper):
              # Overriding the definition that led to adding the current
              # ImplementationProperty.
              return (
                  other.trname == implem.transition.name
                  and (not other.field or other.field == self.state_field)
                  and other.func == implem.implementation)
  
          return False
docs: Checks whether an ImplementationProperty may override an attribute.