“31. We see no reason to suppose that the draftsman of section 167 had in mind any different meaning of occupation from that developed in earlier case law. We draw the conclusion that “occupation” for the purposes of section 167 is a state of affairs which exist when a person:- (i) has physical possession of land – and we take a person to have physical possession of land when he actually uses it for such purposes as he sees fit (subject to any requirement imposed upon him by any agreement relating to the land or restriction to which the land is subject); (ii) controls the use of that land; (iii) has the power of excluding (by trespass action) other persons from the benefit he enjoys in the land; and (iv) has some form of right to some enjoyment of the land.”