Getting the class name of an instance?

Question

How do I find out a name of class that created an instance of an object in Python if the function I am doing this from is the base class of which the class of the instance h

Answer 1

To get instance classname:

type(instance).__name__

or

instance.__class__.__name__

both are the same

Answer 2

In Python 2,

type(instance).__name__ != instance.__class__.__name__
# if class A is defined like
class A():
   ...

type(instance) == instance.__class__
# if class A is defined like
class A(object):
  ...

Example:

>>> class aclass(object):
...   pass
...
>>> a = aclass()
>>> type(a)
<class '__main__.aclass'>
>>> a.__class__
<class '__main__.aclass'>
>>>
>>> type(a).__name__
'aclass'
>>>
>>> a.__class__.__name__
'aclass'
>>>


>>> class bclass():
...   pass
...
>>> b = bclass()
>>>
>>> type(b)
<type 'instance'>
>>> b.__class__
<class __main__.bclass at 0xb765047c>
>>> type(b).__name__
'instance'
>>>
>>> b.__class__.__name__
'bclass'
>>>

Answer 3

Alternatively you can use the classmethod decorator:

class A:
    @classmethod
    def get_classname(cls):
        return cls.__name__

    def use_classname(self):
        return self.get_classname()

Usage:

>>> A.get_classname()
'A'
>>> a = A()
>>> a.get_classname()
'A'
>>> a.use_classname()
'A'

Answer 4

You can simply use __qualname__ which stands for qualified name of a function or class

Example:

>>> class C:
...     class D:
...         def meth(self):
...             pass
...
>>> C.__qualname__
'C'
>>> C.D.__qualname__
'C.D'
>>> C.D.meth.__qualname__
'C.D.meth'

documentation link qualname