How do I use Django's MultiWidget?

The documentation is a bit lacking with respect to this feature.

from django import forms

class TwoInputWidget(forms.MultiWidget):
    """An example widget which concatenates two text inputs with a space"""
    def __init__(self, attrs=None):
        widgets = [forms.TextInput, forms.TextInput]

I can see I need to create a "widgets" property with a list of other widgets, but after that it gets a little Sherlock Holmes.

Would someone please explain to me how to use the MultiWidget widget?