Check If Perfect Square

perfect_square.py

def isPerfectSquare(num):
    beg = 0
    end = num
    while beg <= end:
        mid = (beg + end) // 2
        if mid * mid == num:
            return True
        elif beg == end:
            break
        elif mid * mid > num:
            end = mid
        else:
            beg = mid + 1
    return False