x=7

def f(): x=2
f(); print x
# 7

def g(): global x; x=2

g(); print x
# 2
---------------------------------------
u=[8]

def f(): u[0]=5

f(); print u
# [5]
---------------------------------------
u=[8]

def aumenta (u): u[0]=u[0]+1

aumenta(u); print u
# [9]
---------------------------------------
import mat

x=7

def f ():
  mat.x+=1

f(); print x
# 8
---------------------------------------
x=7

def f ():
  sys.modules[__name__].x+=1

f(); print x
# 8
---------------------------------------
globals()['x']=33
print x
# 33
---------------------------------------
x=33

globals()['x']=33
---------------------------------------
x=7

def f (u):
  print globals()
  print '------------'
  print locals()
  x=3; a=4

f(0)
---------------------------------------
{'f': <function ...>,
'__builtins__': <module ...>,
'__file__': './alfa',
'x': 7, '__name__': '__main__',
'__doc__': None}
------------
{'u': 0}
---------------------------------------
x=7

def f (u):
  x=3; a=4
  print locals()
  x=100

f(0)
# {'a': 4, 'x': 3, 'u': 0}
---------------------------------------
def varauto (a):
  for x in a.split(): globals()[x]=x

varauto('Maria Vera Carla')
print Maria
# Maria
---------------------------------------
pila=[]

# Aggiunge gli argomenti alla pila.
def poni (*v): pila.extend(v)

# Toglie gli ultimi k elementi
# dalla pila. Per k=1 restituisce
# l'ultimo elemento della pila,
# altrimenti la lista degli ultimi
# k elementi.
def togli (k=1):
  if k==1: return pila.pop()
  v=[]
  for i in xrange(k):
    v.append(pila.pop())
  v.reverse(); return v

# Togli gli ultimi due elementi dalla
# pila e aggiunge alla pila la
# loro somma.
def add ():
  a,b=togli(2); pila.append(a+b)
---------------------------------------
import pila

pila.poni(4,3,5,2,10)
print pila.pila
# [4, 3, 5, 2, 10]

print pila.togli()
# 10
print pila.pila
# [4, 3, 5, 2]

pila.add()
print pila.pila
# [4, 3, 7]