Context managers as namespaces. From "Don't Do This" by Richard Jones (https://www.youtube.com/watch?v=H2yfXnUb1S4)

namespace_hack.py

import inspect

class LocalsCapture(object):
  def __enter__(self):
    caller_frame = inspect.currentframe().f_back
    self.local_names = set(caller_frame.f_locals)
    return self
  
  def __exit__(self, exc_type, exc_val, exc_tb):
    caller_frame = inspect.currentframe().f_back
    for name in caller_frame.f_locals:
      if name not in self.local_names:
        self.capture(name, caller_frame.f_locals[name])

class capture_in(LocalsCapture):
  def __init__(self, namespace):
    self.namespace = namespace

  def capture(self, name, value):
    self.namespace[name] = value

class capture_on(LocalsCapture):
  def __init__(self, object):
    self.object = object

  def capture(self, name, value):
    self.object.__dict__[name] = value
    
class capture_globals(capture_in):
  def __init__(self):
    caller_frame = inspect.currentframe().f_back
    super(capture_globals, self).__init__(caller_frame.f_globals)
    
d = {}
with capture_in(d):
  spam = 'ham'
  
print(d)
# {'spam': 'ham'}

class T(object):
  def __init__(self):
    with capture_on(self):
      spam = 'spam'
      ham = 'ham'
      
t = T()
print(t.spam)
# 'spam'

def foo():
  with capture_globals():
    spam = 'ham'
  print(spam)

foo()
# 'ham'
print(spam)
# 'ham'