equi.py

A = [-7, 1, 5, 2, -4, 3, 0]

def equi(A):
    s = [] # array of equilibrium indices
    
    for a in range(len(A)-1): # loop with '0 index' hack
        x = A[:a+1] # split 'left' of the current index
        y = A[a+2:] # split 'right' of the current index
        
        n1 = 0 # this will be the total of the 'left' numbers
        n2 = 0 # this will be the total of the 'right' numbers
        
        for i in x: # add up numbers
            n1 += i
            
        for i in y: # add up numbers
            n2 += i
        
        if n1 == n2: # if two of these numbes are equal, add to array
            s.append(a+1)

    if len(s) > 0: # return indices if there are any, or return -1
        return s
    else:
        return -1  
                
print equi(A)