```
contract Pa {
function a() internal virtual {}
}
contract Child is Pa {
function a() public override {
super.a();
}
}
```
大概就这意思，但是报错
```
TypeError: Overriding function visibility differs.```
`
一开始出现
There was a timeout while attempting to connect to the network at undefined.
Check to see that your provider is valid.
If you have a slow internet connection, try configuring a longer timeout in your Truffle config. Use the networks[networkName].networkCheckTimeout property to do ...