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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 _save_group_field(self, field_type, group):
 """This method packs a group field"""

        
        if field_type == 0x0000:
            # Ignored (commentar block)
            pass
        elif field_type == 0x0001:
            if group.id_ is not None:
                return (4, struct.pack('<I', group.id_))
        elif field_type == 0x0002:
            if group.title is not None:
                return (len(group.title.encode())+1,
                        (group.title+'\0').encode())
        elif field_type == 0x0003:
            if group.creation is not None:
                return (5, self._pack_date(group.creation))
        elif field_type == 0x0004:
            if group.last_mod is not None:
                return (5, self._pack_date(group.last_mod))
        elif field_type == 0x0005:
            if group.last_access is not None:
                return (5, self._pack_date(group.last_access))
        elif field_type == 0x0006:
            if group.expire is not None:
                return (5, self._pack_date(group.expire))
        elif field_type == 0x0007:
            if group.image is not None:
                return (4, struct.pack('<I', group.image))
        elif field_type == 0x0008:
            if group.level is not None:
                return (2, struct.pack('<H', group.level))
        elif field_type == 0x0009:
            if group.flags is not None:
                return (4, struct.pack('<I', group.flags))
        return False