code: def add_activity_form(self, activity_pattern, is_active):
          
          if is_active:
              if activity_pattern not in self.active_forms:
                  self.active_forms.append(activity_pattern)
          else:
              if activity_pattern not in self.inactive_forms:
                  self.inactive_forms.append(activity_pattern)
docs: Adds the pattern as an active or inactive form to an Agent.
  
          Parameters
          ----------
          activity_pattern : dict
              A dictionary of site names and their states.
          is_active : bool
              Is True if the given pattern corresponds to an active state.