code: public ListEntitiesForPolicyResult withPolicyGroups(PolicyGroup... policyGroups) {
          if (this.policyGroups == null) {
              setPolicyGroups(new com.amazonaws.internal.SdkInternalList<PolicyGroup>(policyGroups.length));
          }
          for (PolicyGroup ele : policyGroups) {
              this.policyGroups.add(ele);
          }
          return this;
      }
docs: <p>
  A list of IAM groups that the policy is attached to.
  </p>
  <p>
  <b>NOTE:</b> This method appends the values to the existing list (if any). Use
  {@link #setPolicyGroups(java.util.Collection)} or {@link #withPolicyGroups(java.util.Collection)} if you want to
  override the existing values.
  </p>
  
  @param policyGroups
  A list of IAM groups that the policy is attached to.
  @return Returns a reference to this object so that method calls can be chained together.