NANANANANANANANANANANANA
The construction is letting ${0V_i,1V_j}$ to be the coordinate neighborhoods for XxI. Then
${g_{10,ij}=(g_{01,ji})^{-1}}$. However, when I try to verify the transitive law for
$V_{1,i}\cap V_{0,j}\cap V_{0,k}$, the identity leads to $h_{0,jk}(x)=h_{1,jk}(x)$ which is not right in general.

