Graph Theory, please do not provide answer using any AI$.7\mathrm{.}1\mathrm{.}6.$ Prove that if $T_1$ and $T_2$ are two different spanning trees of a connected

graph, and if $e_1$ is an edge of $T_1$ that is not in $T_2,$ then there is an edge

$e_2$ that is in $T_2$ but not in $T_1$ with the property that $T_2+e_1-e_2$ is a

spanning tree of the graph.