Up to Python 2.1, old-style classes were the only flavour available to the user.
The concept of (old-style) class is unrelated to the concept of type:
if x
is an instance of an old-style class, then x.__class__
designates the class of x
, but type(x)
is always <type
'instance'>
.
This reflects the fact that all old-style instances, independently of
their class, are implemented with a single built-in type, called
instance.
New-style classes were introduced in Python 2.2 to unify the concepts of class and type.
A new-style class is simply a user-defined type, no more, no less.
If x is an instance of a new-style class, then type(x)
is typically
the same as x.__class__
(although this is not guaranteed – a
new-style class instance is permitted to override the value returned
for x.__class__
).
The major motivation for introducing new-style classes is to provide a unified object model with a full meta-model.
It also has a number of immediate benefits, like the ability to
subclass most built-in types, or the introduction of "descriptors",
which enable computed properties.
For compatibility reasons, classes are still old-style by default.
New-style classes are created by specifying another new-style class
(i.e. a type) as a parent class, or the "top-level type" object if no
other parent is needed.
The behaviour of new-style classes differs from that of old-style
classes in a number of important details in addition to what type
returns.
Some of these changes are fundamental to the new object model, like
the way special methods are invoked. Others are "fixes" that could not
be implemented before for compatibility concerns, like the method
resolution order in case of multiple inheritance.
Python 3 only has new-style classes.
No matter if you subclass from object
or not, classes are new-style
in Python 3.
Best Answer
I know it's been said already, but I'd highly recommend the
requests
Python package.If you've used languages other than python, you're probably thinking
urllib
andurllib2
are easy to use, not much code, and highly capable, that's how I used to think. But therequests
package is so unbelievably useful and short that everyone should be using it.First, it supports a fully restful API, and is as easy as:
Regardless of whether GET / POST, you never have to encode parameters again, it simply takes a dictionary as an argument and is good to go:
Plus it even has a built in JSON decoder (again, I know
json.loads()
isn't a lot more to write, but this sure is convenient):Or if your response data is just text, use:
This is just the tip of the iceberg. This is the list of features from the requests site: