def fill_parallel_impl(return_type, arr, val):
    """Parallel implementation of ndarray.fill.  The array on
       which to operate is retrieved from get_call_name and
       is passed along with the value to fill.
    """
    if arr.ndim == 1:
        def fill_1(in_arr, val):
            numba.parfors.parfor.init_prange()
            for i in numba.parfors.parfor.internal_prange(len(in_arr)):
                in_arr[i] = val
            return None
    else:
        def fill_1(in_arr, val):
            numba.parfors.parfor.init_prange()
            for i in numba.pndindex(in_arr.shape):
                in_arr[i] = val
            return None
    return fill_1
Parallel implementation of ndarray.fill.  The array on
       which to operate is retrieved from get_call_name and
       is passed along with the value to fill.
    
numba/parfors/parfor.py