I'm trying to get `toBase10(101)` to spit out `5`. I also need it to work for numbers besides 101, I know that there is a binary converter built into python but I can't figure it out.

Right now I have

```
def toBase10(x):
    int( 'x' , 2 ) == x
    return x

```

I get the error can't convert non-string with explicit base. Why can't I use x in here?