Python numpy: get all combinations of d ints within certain bounds

bound_combinations.py

import numpy as np

def bound_combinations(lmin, lmax):
    """
    example: bound_combinations([1,1], [2,3]) == [[1,1], [1,2], [1,3], [2,1], [2,2], [2,3]]
    """
    assert len(lmax) == len(lmin)
    d = len(lmax)
    # get all the ranges as slices
    ranges = tuple(slice(lmin[i],lmax[i]+1, 1) for i in range(llen))
    # get all combinations and reshape accordingly
    return np.stack(np.mgrid[ranges], axis=llen).reshape((-1,llen))