Write an algorithm that takes in a string and returns a string with balanced parentheses only. The string will contain letters, numbers, and parentheses only.
balanceParens("()") # should return "()"balanceParens("a(b)c)") # should return "a(b)c"balanceParens("(a)(bdd)c)") # should return "(a)(bdd)c"balanceParens("a(dbvb)c)") # should return "a(dbvb)c"balanceParens("a(b)(c)())") # should return "a(b)(c)()"balanceParens(")(") # should return ""balanceParens("(((((") # should return ""balanceParens(")(())(") # should return "(())"balanceParens("(()()(") # should return "()()"balanceParens(")())(()()(") # should return "()()()"