def add_section(self, id_, parent_id, section_type, points):
<EOL>assert id_ not in self.sections, '<STR_LIT>' % id_<EOL>self.sections[id_] = BlockNeuronBuilder.BlockSection(parent_id, section_type, points)<EOL>
add a section

        Args:
            id_(int): identifying number of the section
            parent_id(int): identifying number of the parent of this section
            section_type(int): the section type as defined by POINT_TYPE
            points is an array of [X, Y, Z, R]