content: import React, { Component } from 'react';
  import { Map, TileLayer, Marker, Popup } from 'react-leaflet';
  
  export default class SimpleExample extends Component {
    constructor() {
      super();
      this.state = {
        lat: 51.505,
        lng: -0.09,
        zoom: 13
      };
    }
  
    render() {
      const position = [this.state.lat, this.state.lng];
      return <Map center={position} zoom={this.state.zoom}>
        <TileLayer
          url='http://{s}.tile.osm.org/{z}/{x}/{y}.png'
          attribution='&copy; <a href="http://osm.org/copyright">OpenStreetMap</a> contributors'
        />
        <Marker position={position}>
          <Popup>
            <span>A pretty CSS3 popup. <br/> Easily customizable.</span>
          </Popup>
        </Marker>
      </Map>;
    }
  }
  