JukkaL/mypy — pull request #468 by spkersten (2014-10-02 19:36:28+00:00)
Title: Added semanal error message for assignment to empty tuple

For this snippet:
```python
() = 1
```
mypy used to report `Incompatible types in assignment`, which is not very accurate.

With this PR, the message becomes `Can't assign to ()`, which is in line with Pythons error message.