Remove `del mv[(1,)]`
Remove `del mv[(1,)]`

This isn't what the `del` operator is for, and is more clear as `mv[(1,)] = 0` anyway.
`del` is used to remove an entry from a sequence -but this is neither a sequence, nor is setting to 0 the same as removing.

None of our docs or examples appear to use this.

arsenovic/clifford,arsenovic/clifford