Merge Sort

import time
    '''Merge Sort Function Built By ME!!!!!'''

def Merge(Left, Right, Array):
    
    Left_length = len(Left)
        
    Right_length = len(Right)
    
    i = j = k = 0
        
    while (i < Left_length and j < Right_length):
        
        if Left[i] <= Right[j]:
            Array[k] = Left[i]
            i = i + 1
        
        else:
            Array[k] = Right[j]  
            j = j+ 1
        k = k + 1
        
    # in case one of the letters runs out before the other
    while i < Left_length:
        
        Array[k] = Left[i]
        i = i + 1
        k = k + 1
        
    while j < Right_length:
        
        Array[k] = Right[j]
        j = j + 1
        k = k + 1
        
    return Array

def Merge_Sort(Array): 
    '''Recursive function to sort an Array'''
    n = len(Array)
    
    if n < 2:    
        return
    middle = n // 2
    
        # have to make right and left subarrays        
    Left = Array[0:middle]
        
    Right = Array[middle:]

        #Recursive functions

    Merge_Sort(Left)
    
    Merge_Sort(Right)
    
    # calling the merge function
    Merge(Left, Right, Array)

b = [6,90,1,8,54,67,0,23,900,67,6,8,12,6]
a = [2,4,1,6,8,5,3,7]

start= time.time()

Merge_Sort(a) 
print(a)

End = time.time()

#print('Time to solve algo:', End - start)
Merge_Sort(b)