python2and3.md

Из основного:

• print в 3.х не keyword, а функция.

Feature	Python 2.x	Python 3.x
print	print "a string" или print("a string")	print("a string")
integer division	3 / 2 # 1	3 // 2 # 1
float division	3.0 / 2 # 1.5	3.0 / 2 # 1.5
user input	raw_input("> ")	input("> ")

Dictionaries

Далее d — это словарь (dictionary).

Feature	Python 2.x	Python 3.x
iterating through dict	for key in d.iterkeys():	for key in d:
iterating through dict	for value in d.itervalues():	for value in d.values():
iterating through dict	for (key, value) in d.iteritems():	for (key, value) in d.items():
dict as a list	keylist = d.keys()	keylist = list(d)
dict as a list	valuelist = d.values()	valuelist = list(d.values())

Iterators

Feature	Python 2.x	Python 3.x
xrange	for i in xrange(10):	for i in range(10):
range	for i in range(10):	for i in list(range(10)):
map	new = map(f, old)	new = list(map(f, old))
filter	new = filter(f, old)	new = list(filter(f, old))

Exceptions

Feature	Python 2.x	Python 3.x
raising exceptions	raise ValueError, "something is wrong"	raise ValueError("something is wrong")
catching exceptions	except ValueError, e:	except ValueError as e: