makmanalp

In [1]: class Foo(object):
   ...:     for i in range(3):
   ...:         setattr(Foo, "x"+str(i), i)
   ...:
---------------------------------------------------------------------------
NameError                                 Traceback (most recent call last)
<ipython-input-1-bcc534efdfb8> in <module>()
----> 1 class Foo(object):
      2     for i in range(3):
      3         setattr(Foo, "x"+str(i), i)

makmanalp

In [1]: class Foo(object):
   ...:     for i in range(3):
   ...:         locals()["x" + str(i)] = i
   ...:

In [2]: Foo.x2
Out[2]: 2

makmanalp

In [98]: class Thing(object):
   ....:     import json
   ....:

In [99]: Thing.json
Out[99]: <module 'json' from '.../lib/python3.5/json/__init__.py'>

makmanalp

In [91]: class Thing(object):
        print(locals())
   ....:
{'__qualname__': 'Thing', '__module__': '__main__'}

makmanalp

class Other(object):
    def test(self):
        print("test")
        
o = Other()
o.test()

makmanalp

In [83]: class Foo(object):
            for i in range(3):
                setattr(Foo, "x"+str(i), i)
   ....:

In [84]: Foo.x0
---------------------------------------------------------------------------
AttributeError                            Traceback (most recent call last)
<ipython-input-84-e9bd27bad8bd> in <module>()
----> 1 Foo.x0

makmanalp

# If you legitimately need to get in there before class definition, say because you're generating something that already has a metaclass
# that needs to run (e.g. dynamically generating Django models), you could use type(), like this:
def class_factory_1(num_attrs):
    attrs = {"var_{}".format(i): i for i in range(num_attrs)}
    return type("Klass", (SomeBaseClass,), attrs)

# Otherwise you could use a regular old class definition for a slightly less smartypants solution
def class_factory_2(num_attrs):
    class Inner(object):
        pass

makmanalp

In [17]: class Butter(object):
   ....:     if input("salt?") == "yes":
   ....:         salt = True
   ....:     else:
   ....:         salt = False
   ....:
salt?yes
In [18]: Butter.salt
Out[18]: True

makmanalp

In [8]: class Blah(object):
   ....:     class Blah2(object):
   ....:         pass
   ....:

In [9]: Blah.Blah2
Out[9]: __main__.Blah.Blah2

In [10]: Blah.Blah2()
Out[10]: <__main__.Blah.Blah2 at 0x10c77a630>

makmanalp

In [7]: class Qux(object):
   ...:     raise ValueError
   ...:
---------------------------------------------------------------------------
ValueError                                Traceback (most recent call last)
<ipython-input-7-8d9958c73a44> in <module>()
----> 1 class Qux(object):
      2     raise ValueError
      3