Write a function to generate a 3d array having each element as '*'.
def array_3d(m,n,o):
 array_3d = [[ ['*' for col in range(m)] for col in range(n)] for row in range(o)]
 return array_3d
<s>[INST]<<SYS>>Given a task and its code, generate test cases for the code.<</SYS>>Write a function to generate a 3d array having each element as '*'.
def array_3d(m,n,o):
 array_3d = [[ ['*' for col in range(m)] for col in range(n)] for row in range(o)]
 return array_3d[/INST]assert array_3d(6,4,3)==[[['*', '*', '*', '*', '*', '*'], ['*', '*', '*', '*', '*', '*'], ['*', '*', '*', '*', '*', '*'], ['*', '*', '*', '*', '*', '*']], [['*', '*', '*', '*', '*', '*'], ['*', '*', '*', '*', '*', '*'], ['*', '*', '*', '*', '*', '*'], ['*', '*', '*', '*', '*', '*']], [['*', '*', '*', '*', '*', '*'], ['*', '*', '*', '*', '*', '*'], ['*', '*', '*', '*', '*', '*'], ['*', '*', '*', '*', '*', '*']]]
assert array_3d(5,3,4)==[[['*', '*', '*', '*', '*'], ['*', '*', '*', '*','*'], ['*', '*', '*', '*', '*']], [['*', '*', '*', '*', '*'],['*', '*', '*', '*', '*'], ['*', '*', '*', '*', '*']], [['*', '*', '*', '*', '*'], ['*', '*', '*', '*', '*'], ['*', '*', '*', '*', '*']], [['*', '*', '*', '*', '*'], ['*', '*', '*', '*', '*'], ['*', '*', '*', '*', '*']]]
assert array_3d(1,2,3)==[[['*'],['*']],[['*'],['*']],[['*'],['*']]]</s>