def static_getitem_number_clazz(context, builder, sig, args):
    """This handles the "static_getitem" when a Numba type is subscripted e.g:
    var = typed.List.empty_list(float64[::1, :])
    It only allows this on simple numerical types. Compound types, like
    records, are not supported.
    """
    retty = sig.return_type
    if isinstance(retty, types.Array):
        # This isn't used or practically accessible, but has to exist, so just
        # put in a NULL of the right type.
        res = context.get_value_type(retty)(None)
        return impl_ret_untracked(context, builder, retty, res)
    else:
        # This should be unreachable unless the implementation on the Type
        # metaclass is changed.
        msg = ("Unreachable; the definition of __getitem__ on the "
               "numba.types.abstract.Type metaclass should prevent access.")
        raise errors.LoweringError(msg)
This handles the "static_getitem" when a Numba type is subscripted e.g:
    var = typed.List.empty_list(float64[::1, :])
    It only allows this on simple numerical types. Compound types, like
    records, are not supported.
    
numba/np/arrayobj.py