String to Integer (atoi)

class Solution:

    maxNum = pow(2, 31)

    def myAtoi(self, str):
        """
        :type str: str
        :rtype: int
        """
        isStart = False
        isF = False
        result = 0
        for char in str:
            if not isStart:
                if char == ' ':
                    continue
            elif char not in "0123456789":
                if isF:
                    result = -result
                print(result)
                return result
            
            if char in "+-0123456789":
                isStart = True
                if char == '-':
                    isF = True
                    continue
                elif char == '+':
                    continue
                else:
                    result = result * 10 + int(char)

                    if isF:
                        if -result <= -self.maxNum:
                            result = -self.maxNum
                            print(result)
                            return result
                    else:
                        if result >= self.maxNum - 1:
                            result = self.maxNum - 1
                            print(result)
                            return result
            else:
                if isF:
                    result = -result
                print(result)
                return result

        if isF:
            result = -result
        print(result)
        return result