code: public function setDirection($direction)
      {
          $allowed_values = array('DIVERGENT', 'CONVERGENT', 'MIXED');
          if (!in_array($direction, $allowed_values)) {
              throw new \InvalidArgumentException("Invalid value for 'direction', must be one of 'DIVERGENT', 'CONVERGENT', 'MIXED'");
          }
          $this->container['direction'] = $direction;
  
          return $this;
      }
docs: Sets direction
  @param string $direction
  @return $this