The vertical bar operator in Prolog we use for decompose a list into its head and tail allows us to put more than one item to the left of the operator $($for example, $[$H$1,$ H$2|$ T$]$ is allowed$),$ but does not allow us to put more than one item to the right of the operator $($for example $[$H $|$ T$1,$ T$2]$ is not allowed$).$ Why do you think this is the case?