How to use the victory.VictoryTooltip.defaultEvents function in victory

import React from 'react';
import { VictoryTooltip } from 'victory';
import { Portal } from 'react-portal';
import { Heading } from '../PieCharts/PieCharts.styles';

/* Tooltip */
export class ChartTooltip extends React.Component {
    static defaultEvents = VictoryTooltip.defaultEvents;

    constructor(props) {
        super(props);
        this.state = { position: true, hover: false };
    }

    onMouseEnterHandler = () => {
        this.setState({
            hover: true,
        });
        console.error('enter');
    };
    onMouseLeaveHandler = () => {
        this.setState({
            hover: false,
        });

renderInPortal={false}
          text={this.props.text}
          style={{ fontSize: 30, fill: "#FFF4E5", fontFamily: "roboto"}}
          orientation="top"
          pointerLength={0}
          cornerRadius={125}
          width={250}
          height={250}
          flyoutStyle={{ fill: colorMap(method), stroke: 0}}
        />
      
    );
  }
}

CustomLabel.defaultEvents = VictoryTooltip.defaultEvents;

export default CustomLabel

import React from 'react';
import { VictoryTooltip } from 'victory';

interface IProps {
    text?: string;
    width: number;
    color?: string;
    datum?: any;
}

export class PieLabel extends React.PureComponent {
    public static defaultEvents = VictoryTooltip.defaultEvents;

    public render() {
        const { width, datum } = this.props;

        const labelWidth = width / 2;

        return (