tracing.py

# -*- coding: utf-8 -*-
from __future__ import division, absolute_import, print_function, unicode_literals

import sys

def tracer(frame, event, arg):
    print("source: {}\tlineno: {}".format(frame.f_code.co_filename, frame.f_lineno))
    with open(frame.f_code.co_filename, 'r') as f:
        print(f.readlines()[frame.f_lineno-1][0:-1])
    return tracer

sys.settrace(tracer)

def fib(n):
    ret = None
    if n == 0 or n == 1:
        ret = n
    else:
        ret = fib(n-1) + fib(n-2)
    return ret

print(fib(5))