code: func (c *Redshift) DeleteClusterParameterGroup(input *DeleteClusterParameterGroupInput) (*DeleteClusterParameterGroupOutput, error) {
  	req, out := c.DeleteClusterParameterGroupRequest(input)
  	return out, req.Send()
  }
docs: // DeleteClusterParameterGroup API operation for Amazon Redshift.
  //
  // Deletes a specified Amazon Redshift parameter group.
  //
  // You cannot delete a parameter group if it is associated with a cluster.
  //
  // Returns awserr.Error for service API and SDK errors. Use runtime type assertions
  // with awserr.Error's Code and Message methods to get detailed information about
  // the error.
  //
  // See the AWS API reference guide for Amazon Redshift's
  // API operation DeleteClusterParameterGroup for usage and error information.
  //
  // Returned Error Codes:
  //   * ErrCodeInvalidClusterParameterGroupStateFault "InvalidClusterParameterGroupState"
  //   The cluster parameter group action can not be completed because another task
  //   is in progress that involves the parameter group. Wait a few moments and
  //   try the operation again.
  //
  //   * ErrCodeClusterParameterGroupNotFoundFault "ClusterParameterGroupNotFound"
  //   The parameter group name does not refer to an existing parameter group.
  //
  // See also, https://docs.aws.amazon.com/goto/WebAPI/redshift-2012-12-01/DeleteClusterParameterGroup