Interpreting a Python function from JSON data

问题

I am trying to determine the equivalence of two simple functions passed to python via json like so:

PHP:

$data = array("2*x", "x*2");
$result = shell_exec('python /path/check.py ' . escapeshellarg(json_encode($data)));

Python:

import sys, json
from sympy import *

try:
    data = json.loads(sys.argv[1])
except:
    sys.exit(1)

x = Symbol('x')

response = data[0]
answer = data[1]

result = response==answer

print json.dumps(result)

My assumption is that result returns false because the response and answer are being interpreted as strings. How can I compare these two functions as if I set the variables in python like so:

response = 2*x
answer = x*2

回答1:

You need to convert the strings into SymPy expressions:

sympify(answer) == sympify(response)

来源：https://stackoverflow.com/questions/55931761/interpreting-a-python-function-from-json-data