def projection(self,<EOL>center=None, center_right=None, radius=None, method='<STR_LIT>',<EOL>registration='<STR_LIT>', chirality=Ellipsis, sphere_radius=None,<EOL>pre_affine=None, post_affine=None, tag='<STR_LIT>'):
if chirality is Ellipsis: chirality = self.chirality<EOL>proj = MapProjection(center=center, center_right=center_right, radius=radius,<EOL>method=method, registration=registration, chirality=chirality,<EOL>sphere_radius=sphere_radius,<EOL>pre_affine=pre_affine, post_affine=post_affine)<EOL>return proj(self, tag=tag)<EOL>
topo.projection(...) is equivalent to MapProjection(...)(topo); effectively, this creates
  a map projection object, applies it to the topology topo (yielding a 2D mesh), and
  returns this mesh. To obtain the projection object itself, it is contained in the
  meta_data of the returned mesh (see also MapProjection).