Fixed #13037 -- Added documentation for the css_classes() helper class. Thanks...

    >>> str(f['subject'].errors)

    ''

.. versionadded:: 1.2

When you use Django's rendering shortcuts, CSS classes are used to

indicate required form fields or fields that contain errors. If you're

manually rendering a form, you can access these CSS classes using the

``css_classes`` method::

	>>> f = ContactForm(data)

	>>> f['message'].css_classes()

	'required'

If you want to provide some additional classes in addition to the

error and required classes that may be required, you can provide

those classes as an argument::

	>>> f = ContactForm(data)

	>>> f['message'].css_classes('foo bar')

	'foo bar required'

.. _binding-uploaded-files:

Binding uploaded files to a form