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Solve the following problem using Python, implementing the functions described below, one line at a time
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Description:
 def defaults(self):
 """Default filter form data when no GET data is provided."""

        # Set default date span to previous week.
        (start, end) = get_week_window(timezone.now() - relativedelta(days=7))
        return {
            'from_date': start,
            'to_date': end,
            'billable': True,
            'non_billable': False,
            'paid_leave': False,
            'trunc': 'day',
            'projects': [],
        }