please help making a loop faster

[mrnapoli]

"""
Inputs:
- x_i: A numpy array of images of shape (H, W)
- w_l: A numpy array of weights of shape (H, W)
- b_l: A float (single number)

Returns:
- out: A float (single number)
"""
N, H, W = x.shape
M, _, _ = w.shape
out = np.zeros((N,M))