<SYSTEM_TASK:>
Solve the following problem using Python, implementing the functions described below, one line at a time
<END_TASK>
<USER_TASK:>
Description:
 def is_edge(obj, shape):
 """ Check if a 2d object is on the edge of the array. Parameters obj : tuple(slice, slice) Pair of slices (e.g. from scipy.ndimage.measurements.find_objects) shape : tuple(int, int) Array shape. Returns ------- b : boolean True if the object touches any edge of the array, else False. """


    if obj[0].start == 0: return True
    if obj[1].start == 0: return True
    if obj[0].stop == shape[0]: return True
    if obj[1].stop == shape[1]: return True
    return False