Error in Exercise 4 and 5 not solving

Course Q&A Natural Language Processing NLP with Probabilistic Models
1 
# UNIT TEST COMMENT: Candidate for Table Driven Tests
# UNQ_C4 GRADED FUNCTION: back_prop
def back_prop(x, yhat, y, h, W1, W2, b1, b2, batch_size):
    '''
    Inputs: 
        x:  average one hot vector for the context 
        yhat: prediction (estimate of y)
        y:  target vector
        h:  hidden vector (see eq. 1)
        W1, W2, b1, b2:  matrices and biases  
        batch_size: batch size 
     Outputs: 
        grad_W1, grad_W2, grad_b1, grad_b2:  gradients of matrices and biases   
    '''
    ### START CODE HERE (Replace instanes of 'None' with your code) ###
    # {Moderator's Edit: Solution Code Removed}
    ### END CODE HERE ####
    print(f'batch_size = {batch_size} and x.shape = {x.shape}')
    return grad_W1, grad_W2, grad_b1, grad_b2
2

Hey @DURGESH_RAO,
Please check out the following thread. For future references, it is strictly against the community guidelines to share the solution code publicly. You are more than welcome to share your error stack.

Cheers,
Elemento