Let $\{ X_t : t \in T\}$, be a family of topological spaces. Suppose thst $T = \bigcup \{ T_s : s \in S \}$, where $T_s \neq \emptyset $ for all $s \in S$, and $T_s \cap T_{s'} = \emptyset$ if $s \neq s'$.
How can I prove that $\Pi_{t \in T} X_t$ and $\Pi_{s \in S}(\Pi_{t \in T_s} X_t)$ are homeomorphic.
Intuitively, it seems rather obvious. But, the formal proof, unfortunately, I am not sure where to start..
Any help?
Thank you!