check a balanced Parenthesis

balancedParenthesis.py

# (){}[]

def isBalancedParenthesis(str):
    stack = []

    for i in str:
        if i == '(' or i == '{' or i == '[':
            stack.append(i)
        elif i == ')' or i == '}' or i == ']':

            if len(stack) == 0:
                return False
            else:
                if stack[-1] == '(' and i == ')' or stack[-1] == '{' and i == '}' or stack[-1] == '[' and i == ']':
                    stack.pop()

    if len(stack) == 0:
        return True
    else:
        return False


# TEST
str = '()(){}[{()}]'
str2 = '[(a+b)*c] - (d+c)*{b*9}'
print(isBalancedParenthesis(str))
print(isBalancedParenthesis(str2))