Stupid way to pickle traceback objects in Python

tbpack.py

import sys
import types


def _patched_name(code, name):
    # argument order is described in help(types.CodeType)
    return types.CodeType(
        code.co_argcount,
        code.co_nlocals,
        code.co_stacksize,
        code.co_flags,
        code.co_code,
        code.co_consts,
        code.co_names,
        code.co_varnames,
        code.co_filename,
        name,
        code.co_firstlineno,
        code.co_lnotab,
        code.co_freevars,
        code.co_cellvars,
    )


def pack(tb):
    result = []
    while tb is not None:
        code = tb.tb_frame.f_code
        result.append((code.co_filename, tb.tb_lineno, code.co_name))
        tb = tb.tb_next
    return result


def unpack(packed):
    prev_var = '_e'
    globs = {prev_var: ZeroDivisionError}
    for i, (filename, lineno, name) in enumerate(reversed(packed)):
        this_var = '_%d' % i
        eval(compile('%sdef %s(): raise %s()' % ('\n' * (lineno - 1), this_var, prev_var), filename, 'exec'), globs)
        prev_var = this_var
        func = globs[this_var]
        func.func_code = _patched_name(func.func_code, name)
    try:
        globs[prev_var]()
    except ZeroDivisionError:
        globs.clear()
        return sys.exc_info()[2].tb_next


# import copy_reg
# copy_reg.pickle(types.TracebackType, lambda obj: (unpack, (pack(obj), )))