如何从有效负载中传入的字符串值中获取值，

payload = "name=John&age=30&gender=Male"

def get_value_from_payload(key):
    pairs = payload.split("&")
    for pair in pairs:
        kv = pair.split("=")
        if kv[0] == key:
            return kv[1]
    return None

name = get_value_from_payload("name")
age = get_value_from_payload("age")
gender = get_value_from_payload("gender")

print(name)    # Output: John
print(age)     # Output: 30
print(gender)  # Output: Male

import re

payload = "name=John&age=30&gender=Male"

def get_value_from_payload(key):
    pattern = r"{}=([^&]+)".format(key)
    match = re.search(pattern, payload)
    if match:
        return match.group(1)
    return None

name = get_value_from_payload("name")
age = get_value_from_payload("age")
gender = get_value_from_payload("gender")

print(name)    # Output: John
print(age)     # Output: 30
print(gender)  # Output: Male