import re
def checkio(expression):
pattern = '({}|\[\]|\(\))'
matcher = re.compile(pattern)
brackets = ''.join(x for x in expression if x in '{}[]()')
while True:
m = matcher.search(brackets)
if not m: break
brackets = brackets.replace(m.group(), '')
return False if brackets else True
#These "asserts" using only for self-checking and not necessary for auto-testing
if __name__ == '__main__':
assert checkio("((5+3)*2+1)") == True, "Simple"
assert checkio("{[(3+1)+2]+}") == True, "Different types"
assert checkio("(3+{1-1)}") == False, ") is alone inside {}"
assert checkio("[1+1]+(2*2)-{3/3}") == True, "Different operators"
assert checkio("(({[(((1)-2)+3)-3]/3}-3)") == False, "One is redundant"
assert checkio("2+3") == True, "No brackets, no problem"
https://www.checkio.org/mission/brackets/