Nitpick:
I wasn't clear, what I mean is that the convention is either to have

```
from scipy.sparse import csc_matrix
from scipy.sparse import csr_matrix
from scipy.sparse import coo_matrix
from scipy.sparse import dok_matrix
from scipy.sparse import csc_matrix
from scipy.sparse import lil_matrix
``` 
which  works nicely with git
or to have (fewer module follow this convention)
```
from scipy.sparse import (csc_matrix, csr_matrix, coo_matrix, dok_matrix, 
                          lil_matrix)
```
?

We also try to avoid ` \`.