How To Create Objects On The Fly In Python?

How do I create objects on the fly in Python? I often want to pass information to my Django templates which is formatted like this: {'test': [a1, a2, b2], 'test2': 'something else'

Solution 1:

You can use built-in type function:

testobj = type('testclass', (object,), 
                 {'test':[a1,a2,b2], 'test2':'something else', 'test3':1})()

But in this specific case (data object for Django templates), you should use @Xion's solution.

Solution 2:

In Django templates, the dot notation (testobj.test) can resolve to the Python's [] operator. This means that all you need is an ordinary dict:

testobj = {'test':[a1,a2,b2], 'test2':'something else', 'test3':1}

Pass it as testobj variable to your template and you can freely use {{ testobj.test }} and similar expressions inside your template. They will be translated to testobj['test']. No dedicated class is needed here.

Solution 3:

There is another solution in Python 3.3+types.SimpleNamespace

from types import SimpleNamespace
test_obj = SimpleNamespace(a=1, b=lambda: {'hello': 42})

test_obj.a
test_obj.b()

Solution 4:

Use collections.namedtuple.

Solution 5:

use building function type: document

>>>classX:...    a = 1...>>>X = type('X', (object,), dict(a=1))

first and second X are identical