def foo(x, y):
  print x, y
 
alist = [1, 2]
adict = {'x': 1, 'y': 2}
 
foo(*alist) # 1, 2
foo(**adict) # 1, 2

> x = 3
> 1 < x < 5
True
> 4 > x >=3
True

> def foo(x=[]):
...   x.append(1)
...   print x
...
> foo()
[1]
> foo()
[1, 1]

> def foo(x=None):
...   if x is None:
...     x = []
...   x.append(1)
...   print x
...
> foo()
[1]
> foo()
[1]
>

sum[value] = sum.get(value, 0) + 1

> print "Hello %(name)s !" % {'name': 'James'}
Hello James !
> print "I am years %(age)i years old" % {'age': 18}
I am years 18 years old

> print "Hello {name} !".format(name="James")
Hello James !

> for i in (1, 3, 5):
...   if i % 2 == 0:
...     break
... else:
...   print "var i is always an odd"
...
var i is always an odd
>

> class Dict(dict):
...  def __missing__(self, key):
...   self[key] = []
...   return self[key]
...
> dct = Dict()
> dct["foo"].append(1)
> dct["foo"].append(2)
> dct["foo"]
[1, 2]

> from collections import defaultdict
> dct = defaultdict(list)
> dct["foo"]
[]
> dct["bar"].append("Hello")
> dct
defaultdict(<type 'list'>, {'foo': [], 'bar': ['Hello']})

> Name = "Wang" "Hong"
> Name
'WangHong'

> Name = "Wang" ... "Hong"
> Name
'WangHong'
10. Python解释器中的”_”
 
> range(4)
[0, 1, 2, 3]
> _
[0, 1, 2, 3]

import this

> [(i, j) for i in range(3) for j in range(i)]
[(1, 0), (2, 0), (2, 1)]
14. try/except/else
 
try:
 put_4000000000_volts_through_it(parrot)
except Voom:
 print "'E's pining!"
else:
 print "This parrot is no more!"
finally:
 end_sketch()

> print  open("somefile", "w+"), "Hello World"

Python 3.2 (r32:88445, Oct 20 2012, 14:09:50)
[GCC 4.5.2] on linux2
Type "help", "copyright", "credits" or "license" for more information.
> ...
Ellipsis

> class C(object):
... def __getitem__(self, item):
...  return item
...
> C()[1:2, ..., 3]
(slice(1, 2, None), Ellipsis, 3)
>

> a, b, *rest = range(10)
> a
0
> b
1
> rest
[2, 3, 4, 5, 6, 7, 8, 9]
>

> first, second, *rest, last = range(10)
> first
0
> second
1
> last
9
> rest
[2, 3, 4, 5, 6, 7, 8]

> pow(4, 2, 2)
0
> pow(4, 2, 3)
1

> lst = ["a", "b", "c"]
> list(enumerate(lst, 1))
[(1, 'a'), (2, 'b'), (3, 'c')]

> set([1,2,3])

> {1,2,3}
set([1, 2, 3])

> a = [1, 2, 3, 4, 5, 6, 7]
> a[1:4] = []
> a
[1, 5, 6, 7]

> a = [0, 1, 2, 3, 4, 5, 6, 7]
> del a[::2]
> a
[1, 3, 5, 7]

> isinstance(1, (float, int))
True
> isinstance(1.3, (float, int))
True
> isinstance("1.3", (float, int))
False

> isinstance("1.3", (float, int, str))
True

> a, b = {}, {}
> a['b'] = b
> b['a'] = a
> a
{'b': {'a': {...}}}

> a, b = [], []
> a.append(b)
> b.append(a)
> a
[[[...]]]

> int(u'1234')
1234

 
> class O(object):pass
...
> o = O()
> setattr(o, "can't touch this", 123)
> o.can't touch this
 File "<stdin>", line 1
  o.can't touch this
           ^
SyntaxError: EOL while scanning string literal
>
 File "<stdin>", line 1
  o.can't touch this
           ^
SyntaxError: EOL while scanning string literal