a = 42
def foo():
  a = 13
  print "globals: %s" % globals()
  print "locals: %s" % locals()
  return a
foo()
print "a: %d" % a

globals: {'a': 42, '__builtins__': <module '__builtin__' (built-in)>, '__file__': 'C:\\Users\\h\\Desktop\\test4.py', '__package__': None, '__name__': '__main__', 'foo': <function foo at 0x0000000002C17AC8>, '__doc__': None}
locals: {'a': 13}
a: 42

a = 42
def foo():
  a += 1
  return a
foo()

a = 42
def foo():
  global a
  a = 13
  print "globals: %s" % globals()
  print "locals: %s" % locals()
  return a
foo()
print "a: %d" % a

globals: {'a': 13, '__builtins__': <module '__builtin__' (built-in)>, '__file__': 'C:\\Users\\h\\Desktop\\test4.py', '__package__': None, '__name__': '__main__', 'foo': <function foo at 0x0000000002B87AC8>, '__doc__': None}
locals: {}
a: 13

def countdown(start):
  n = start
  def display():
    print n
  def decrement():
    n -= 1
  while n > 0:
    display()
    decrement()
countdown(10)

def countdown(start):
  alist = []
  alist.append(start)
  def display():
    print alist[0]
  def decrement():
    alist[0] -= 1
  while alist[0] > 0:
    display()
    decrement()
countdown(10)

def countdown(start):
  n = start
  def display():
    print n
  def decrement():
    nonlocal n
    n -= 1
  while n > 0:
    display()
    decrement()
countdown(10)

def foo():
  x = 12
  def bar():
    print x
  return bar
foo()()

>>> def foo():
    x = 12
    def bar():
      return x
    return bar
 
>>> foo.func_code.co_cellvars
('x',)
>>> bar = foo()
>>> bar.func_code.co_freevars
('x',)

>>> bar.func_closure
(<cell at 0x0000000003512C78: int object at 0x0000000000645D80>,)

>>> bar.func_closure[0].cell_contents
12

>>> def foo():
    x = 12
    def bar():
      pass
    return bar
 
>>> bar = foo()
>>> print bar.func_closure
None

>>> def foo(n):
    return n * i
 
>>> fs = [foo for i in range(4)]
>>> print fs[0](1)

def foo():
  fs = []
  for i in range(4):
    fs.append(lambda x: x*i)
  return fs
for f in foo():
  print f(1)

>>> fs = [lambda x, i=i: x * i for i in range(4)]
>>> for f in fs:
    print f(1)

>>> def foo(i):
    return lambda x: x * i
 
>>> fs = [foo(i) for i in range(4)]
>>> for f in fs:
    print f(1)

>>> for f in map(lambda i: lambda x: i*x, range(4)):
    print f(1)

>>> fs = [functools.partial(lambda x, i: x * i, i) for i in range(4)]
>>> for f in fs:
    print f(1)