Transfers of value are exempt to the extent that the values transferred by them—
are attributable to property which becomes the property of a political party qualifying for exemption under this section; . . .
. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
A political party qualifies for exemption under this section if, at the last general election preceding the transfer of value,—
two members of that party were elected to the House of Commons, or
one member of that party was elected to the House of Commons and not less than 150,000 votes were given to candidates who were members of that party.
Subsections (2) to (5) of section 23 above shall apply in relation to subsection (1) above as they apply in relation to section 23(1).
For the purposes of section 23(2) to (5) as they apply by virtue of subsection (3) above property is given to any person or body if it becomes the property of or is held on trust for that person or body, and "donor" shall be construed accordingly.