def METHOD_NAME(self):
    range_start_dt = self.cleaned_data.get('range_start_dt')
    if range_start_dt:
        try:
            range_start_dt = datetime.strptime(range_start_dt, '%m/%d/%Y')
        except ValueError:
            range_start_dt = None
            self._errors['range_start_dt'] = ['Invalid date selected.']
    else:
        range_start_dt = None
    return range_start_dt