How to use the react-native-ui-lib.Colors.dark50 function in react-native-ui-lib

console.log('press on a card')}>

{_.map(Typography, (value, key) => {
          return (
            
          );
        })}

height={75.8}
          onPress={item.listOnPress}
        >
          
            
          
          
            
              
              
            
            
              
              {item.count &gt; 0 &amp;&amp; <button label="{item.count}" size="{'small'}">}
            
          
        
      
    );
  }
}</button>

import _ from 'lodash';
import PropTypes from 'prop-types';
import React from 'react';
import {StyleSheet, PanResponder, ViewPropTypes, AccessibilityInfo} from 'react-native';
import {Constants, Colors, PureBaseComponent, View} from 'react-native-ui-lib';

const TRACK_SIZE = 6;
const THUMB_SIZE = 24;
const BORDER_WIDTH = 6;
const SHADOW_RADIUS = 4;
const DEFAULT_COLOR = Colors.dark50;
const ACTIVE_COLOR = Colors.violet30;
const INACTIVE_COLOR = Colors.dark60;

/**
 * @description: A Slider component
 * @example: https://github.com/wix/react-native-ui-lib/blob/feat/new_components/demo/src/screens/componentScreens/SliderScreen.js
 */
export default class Slider extends PureBaseComponent {
  static displayName = 'Slider';

  static propTypes = {
    /**
     * Initial value
     */
    value: PropTypes.number,
    /**

imageSource: {
      uri:
        'https://lh3.googleusercontent.com/-cw77lUnOvmI/AAAAAAAAAAI/AAAAAAAAAAA/WMNck32dKbc/s181-c/104220521160525129167.jpg',
    },
    badgeProps: {size: 'pimpleBig', backgroundColor: Colors.yellow30},
    badgePosition: 'BOTTOM_RIGHT',
  },

  {
    title: 'Smaller size, Badge ("offline")',
    size: 40,
    imageSource: {
      uri:
        'https://lh3.googleusercontent.com/-CMM0GmT5tiI/AAAAAAAAAAI/AAAAAAAAAAA/-o9gKbC6FVo/s181-c/111308920004613908895.jpg',
    },
    badgeProps: {size: 'pimpleBig', backgroundColor: Colors.dark50},
    badgePosition: 'BOTTOM_LEFT',
  },
  {
    title: 'Image with fade in animation',
    size: 60,
    animate: true,
    imageProps: {animationDuration: 1000},
    imageSource: {uri: 'https://static.pexels.com/photos/60628/flower-garden-blue-sky-hokkaido-japan-60628.jpeg'},
  },
  {
    title: 'Big pimple',
    size: 70,
    backgroundColor: 'red',
    imageSource: {
      uri: 'https://randomuser.me/api/portraits/women/24.jpg',
    },