client.on('voiceStateUpdate', (oldState, newState) => {
if(oldState.channelID === newState.channelID) {
console.log('a user has not moved!')
}
if(oldState.channelID != null && newState.channelID != null && newState.channelID != oldState.channelID) {
console.log('a user switched channels')
}
if(oldState.channelID === null) {
console.log('a user joined!')
}
if (newState.channelID === null) {
console.log('a user left!')
}
});