A little function that recives a list, return equilibrium index (-1 when no equilibrium index is found) or index+1 (only when the sum of all list components is equal to zero) and returns another list with solutions

equi.py

# A is a list object
def equi ( A ):
	# solution will store all solutions to the problem
	solution = list()
	# the sum of all list components 
	A_sum = 0
	# iterates for each element in the list
	for index in range( len( A ) ):
		A_sum += A[index]
		# stores the sum of all components at left of this index position
		sumaizq = 0
		# stores the sum of all components at right of this index position
		sumader = 0
		
		for i in range( index ):
			sumaizq += A[i]
		for i in range( index + 1, len( A ) ):
			sumader += A[i]
		if sumader == sumaizq:
			solution.append( index )
	# if no equilibrium point was found, then add -1 to solution.
	if len(solution) == 0:
		solution.append( -1 )
	# if the sum of all elements of the list is equal to 0, then add the length-1 of the list
	if A_sum == 0:
		solution.append( len( A ) - 1 )
	return solution