code: def _assemble_regulate_amount(stmt):
      
      obj_str = _assemble_agent_str(stmt.obj)
      if stmt.subj is not None:
          subj_str = _assemble_agent_str(stmt.subj)
          if isinstance(stmt, ist.IncreaseAmount):
              rel_str = ' increases the amount of '
          elif isinstance(stmt, ist.DecreaseAmount):
              rel_str = ' decreases the amount of '
          stmt_str = subj_str + rel_str + obj_str
      else:
          if isinstance(stmt, ist.IncreaseAmount):
              stmt_str = obj_str + ' is produced'
          elif isinstance(stmt, ist.DecreaseAmount):
              stmt_str = obj_str + ' is degraded'
      return _make_sentence(stmt_str)
docs: Assemble RegulateAmount statements into text.