import json
import hashlib
payload = {'key1': 'value1', 'key2': 'value2'}
k = 'key'.encode()
y = json.dumps(payload).encode()
m = hashlib.md5(y+k).hexdigest()
print(m)
CmltcG9ydCBqc29uCmltcG9ydCBoYXNobGliCgpwYXlsb2FkID0geydrZXkxJzogJ3ZhbHVlMScsICdrZXkyJzogJ3ZhbHVlMid9CgprID0gJ2tleScuZW5jb2RlKCkKeSA9IGpzb24uZHVtcHMocGF5bG9hZCkuZW5jb2RlKCkKbSA9IGhhc2hsaWIubWQ1KHkraykuaGV4ZGlnZXN0KCkKcHJpbnQobSk=