python实现一个计算器

def change_list(data):
    data_list = []
    for i in data.strip():
        if i == " ":
            continue
        data_list.append(i)
    print(data_list)
    num = 0
    try:
        while 1:
            if data_list[0] == "-":
                data_list[0] = data_list[0] + data_list[1]
                data_list.pop(1)
            if data_list[num].isnumeric():
                if data_list[num+1].isnumeric():
                    data_list[num] = data_list[num] + data_list[num+1]
                    data_list.pop(num+1)
                else:
                    num += 1
            else:
                num += 1
    except IndexError as e:
        return data_list


def compute(data):
    while 1:
        #判断乘除
        if "*" in data or "/" in data:
            for i,j in enumerate(data):
                if j == "*":
                    data[i+1] =int(data[i-1]) * int(data[i+1])
                    data.pop(i-1)
                    data.pop(i-1)
                    break
                if j == "/":
                    data[i+1] =int(data[i-1]) * int(data[i+1])
                    data.pop(i-1)
                    data.pop(i-1)
                    break
        #判断加减
        if "+" in data or "-" in data:
            for i,j in enumerate(data):
                if j == "+":
                    data[i + 1] = int(data[i - 1]) + int(data[i + 1])
                    data.pop(i - 1)
                    data.pop(i - 1)
                    break
                if j == "-":
                    data[i + 1] = int(data[i - 1]) - int(data[i + 1])
                    data.pop(i - 1)
                    data.pop(i - 1)
                    break
        else:
            return data

def parench(data):
	"""算括号"""
    if "(" in data:
        while 1:
            if ")" in data:
                b = data.index(")")
                for i in range(b, -1, -1):
                    if data[i] == "(":
                        new_list = []
                        new_list = data[i+1:b]
                        byte = compute(new_list)[0]
                        del(data[i:b+1])
                        data.insert(i,byte)
                        break
            else:
                return compute(data)
    else:
        compute(data)

while 1:
    data = input("请输入算数:")
    if data == "": continue
    data = change_list(data)
    parench(data)
    print(data[0])
    if input("如果输入q则退出:\n") == "q":
        exit()