Python – Getting the Class Name of an Instance

instanceofintrospectionpythonpython-datamodel

How do I find out the name of the class used to create an instance of an object in Python?

I'm not sure if I should use the inspect module or parse the __class__ attribute.

Best Answer

Have you tried the __name__ attribute of the class? ie type(x).__name__ will give you the name of the class, which I think is what you want.

>>> import itertools
>>> x = itertools.count(0)
>>> type(x).__name__
'count'

If you're still using Python 2, note that the above method works with new-style classes only (in Python 3+ all classes are "new-style" classes). Your code might use some old-style classes. The following works for both:

x.__class__.__name__

Related Solutions

Python – Get Class that Defined Method

import inspect

def get_class_that_defined_method(meth):
    for cls in inspect.getmro(meth.im_class):
        if meth.__name__ in cls.__dict__: 
            return cls
    return None

Python – Get Fully Qualified Class Name of an Object

With the following program

#!/usr/bin/env python

import foo

def fullname(o):
    klass = o.__class__
    module = klass.__module__
    if module == 'builtins':
        return klass.__qualname__ # avoid outputs like 'builtins.str'
    return module + '.' + klass.__qualname__

bar = foo.Bar()
print(fullname(bar))

and Bar defined as

class Bar(object):
  def __init__(self, v=42):
    self.val = v

the output is

$ ./prog.py
foo.Bar

If you're still stuck on Python 2, you'll have to use __name__ instead of __qualname__, which is less informative for nested classes - a class Bar nested in a class Foo will show up as Bar instead of Foo.Bar:

def fullname(o):
    klass = o.__class__
    module = klass.__module__
    if module == '__builtin__':
        return klass.__name__ # avoid outputs like '__builtin__.str'
    return module + '.' + klass.__name__

Best Answer

Related Solutions

Python – Get Class that Defined Method

Python – Get Fully Qualified Class Name of an Object

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