getting attributes and methods of class without creating object

[Patrick Maupin]

On May 17, 10:52 pm, shuvro <shuvr... at gmail.com> wrote:
> Suppose I have a class like this -
>
> class myClass(object):
>
>     def __init__(self):
>         self.a = 10
>         self.b = 20
>
>     def my_method(self,var = 20):
>         self.local_var = var
>
> I want to know about its method(__init__ and my_method) and
> variables(a,b, local_var) without creating the object of it. I tried
> getmembers function of inspect module. But it can do this with an
> object of myClass as argument. Like
>
> import inspect
> var = myClass()
> inspect.getmembers(var)
>
> I have to know about this without creating the object of myClass.
> Can anyone help me please?

Well, you can do the same thing with myClass itself:

inspect.getmembers(myClass)

But that won't show you a,b, or local_var, because those don't belong
to the class.  They only belong to class instances, and maybe even not
all class instances.  (For example, if my_method is not called, then
the instance won't have local_var defined.)

Python is a very dynamic language, and class instances (and even the
classes themselves!) can be modified at any time during execution.
You don't even have to be executing inside a class's function to add
stuff to it:

class foo:
    pass

bar = foo()
bar.a = 3


So to "know" about the attributes of an instance of a class without
actually creating that instance is very difficult.  You didn't specify
why you want to do this, but often the reason is to try to catch
potential errors without actually running code.  This is typically
called "linting", and there are a few Python packages designed to do
this, such as pylint and pychecker.  Probably others, but I don't know
anything about them, because I find that in most cases, the best way
to test or to reason about Python code is to actually run it.

Regards,
Pat