<SYSTEM_TASK:>
Solve the following problem using Python, implementing the functions described below, one line at a time
<END_TASK>
<USER_TASK:>
Description:
 def calcMse(predTst, yTest, axis=0):
 """calculate mean squared error. Assumes that axis=0 is time Parameters predTst : np.array, predicted reponse for yTest yTest : np.array, acxtually observed response for yTest Returns ------- aryFunc : np.array MSE """

    return np.mean((yTest - predTst) ** 2, axis=axis)