2recursion.py

# Python Program to find sum
# of nested list using Recursion

def sum_nestedlist( l ):

	# specify that global variable is
	# referred to here in this function
	total = 0
	
	for j in range(len(l)):
	
		if type(l[j]) == list :
		
			# call the same function if
			# the element is a list
			total+= sum_nestedlist(l[j])
		else:
		
			# if it's a single element
			# and not a list, add it to total
			total += l[j]
			
	return total
			
print(sum_nestedlist([[1,2,3],[4,[5,6]],7]))