Django snippets

class SplitTimeField(forms.MultiValueField):
    """
    Field written to accept two fields Hour Field and Time Field
    and combine them into TimeField.
    """
    default_error_messages = {
        'invalid_time': _(u'Enter a valid time.'),
    }    

    def __init__(self, *args, **kwargs):
        errors = self.default_error_messages.copy()
        if 'error_messages' in kwargs:
            errors.update(kwargs['error_messages'])
        fields = (
            forms.CharField(error_messages={'invalid': errors['invalid_time']}),
            forms.CharField(error_messages={'invalid': errors['invalid_time']}),
        )
        super(SplitTimeField, self).__init__(fields, *args, **kwargs)

    def compress(self, data_list):
        if data_list:
            # Raise a validation error if time or date is empty
            # (possible if SplitDateTimeField has required=False).
            if data_list[0] in (None, '') or data_list[1] in (None, ''):
                raise forms.ValidationError(self.error_messages['invalid_time'])
            return datetime.time(int(data_list[0]),int(data_list[1]))
        return None

class SplitTimeWidget(forms.MultiWidget):
    """
    Widget written to split widget into hours and minutes.
    """
    def __init__(self, attrs=None):
        widgets = (
                    forms.Select(attrs=attrs, choices=([(hour,hour) for hour in range(0,24)])), \
                    forms.Select(attrs=attrs, choices=([(minute, str(minute).zfill(2)) for minute in [0,15,30,45]]))
                  )
        super(SplitTimeWidget, self).__init__(widgets, attrs)

    def decompress(self, value):
        if value:
            return [value.hour, value.minute]
        return [None, None]