Suppose the input set $\backslash$Sigma as $\{$a$,$ b$\}$ and the language X is defined as follows:

X $=\{$s in $\backslash$Sigma $|$ s $=$ sR$\},$

Here sR means the reverse of s$.$ For example, if s$=$bbaa, then sR$=$aabb.

$(1)$ Give a context$-$free grammar G that describes language X$.$ Make sure to specify G as a $4-$tuple G $=($V$,\backslash$Sigma $,$ R$,$ S$).$