[python] Mergesort with Python

#here is my answer using two function one for merge and another for divide and 
 #conquer 
l=int(input('enter range len'))      
c=list(range(l,0,-1))
print('list before sorting is',c)
def mergesort1(c,l,r):    
    i,j,k=0,0,0
    while (i<len(l))&(j<len(r)):
        if l[i]<r[j]:
            c[k]=l[i]
            i +=1            
        else:
            c[k]=r[j]
            j +=1
        k +=1
    while i<len(l):
        c[k]=l[i]
        i+=1
        k+=1
    while j<len(r):
        c[k]=r[j]
        j+=1
        k+=1
    return c   
def mergesort(c):
    if len(c)<2:
        return c
    else:
        l=c[0:(len(c)//2)]
        r=c[len(c)//2:len(c)]
        mergesort(l)
        mergesort(r)
    return    mergesort1(c,l,r)