Function matrix_slice_mut_from_numpy 

pub unsafe fn matrix_slice_mut_from_numpy<'a, N, R, C>(
    _py: Python<'_>,
    input: &'a PyAny,
) -> Result<MatrixSliceMut<'a, N, R, C, Dynamic, Dynamic>, Error>
where
    N: Scalar + Element,
    R: Dim,
    C: Dim,

Create a mutable nalgebra view from a numpy array.

The array dtype must match the output type exactly. If desired, you can convert the array to the desired type in Python using numpy.ndarray.astype.

Safety

This function creates a mutable slice that references data owned by Python. The user must ensure that no other Rust references to the same data exist.