echoeval.py

#!/usr/bin/env python3

def echoeval(expr_str):
    global sys, pprint
    try: sys
    except NameError: import sys
    try: pprint
    except NameError: from pprint import pprint
    calling_frame = sys._getframe().f_back
    print(expr_str, '=', end=' ')
    pprint(eval(expr_str, calling_frame.f_locals, calling_frame.f_globals))

if __name__ == '__main__':

    num = 3.14

    class A:
        hello = 'Hello World!'

    def f(x):
        echoeval('num')
        echoeval('num * 2')
        echoeval('A.hello')
        echoeval('x')

    f([1, 2, 3])

    # Output:
    # num = 3.14
    # num * 2 = 6.28
    # A.hello = 'Hello World!'
    # x = [1, 2, 3]

I use this Log function:

#!/usr/bin/python

from __future__ import print_function

import sys

from pprint import pprint

def Log(var_str='', pre='', post=''):
    if pre:
        print(pre, end=' ')
    if var_str:
        print(var_str, end=': ')
        calling_frame = sys._getframe().f_back
        pprint(eval(var_str, calling_frame.f_locals, calling_frame.f_globals))
    print(post)

test = "okok!"

Log('test', pre="pre", post="post")

# Output:
# pre test: 'okok!'
# post

Thank you!!