5. (CLO 5 - Grammar construction.)
A palindrome is a word that can be read from left to right the same as from right to left.
Find a grammar that will generate all palindromes for the alphabet $\Sigma = \{a, b, c\}$. Notice that
the alphabet has three letters here a, b, and c.
$L = \{w \in \{a, b, c\}^* : w = w^R\}$