Given a string s, return the length of the longest good palindromic subsequence in s.

A string is considered a good palindromic subsequence if:

• It is a subsequence of s.

• It is a palindrome.

• Its length is an even number.

• No two consecutive characters are identical, except for the two middle characters (that is, for a string of length $k$, the character at index $i$ does not equal the character at index $i + 1$ for all $0 \leq i < \frac{k}{2} - 1$).

Note: A subsequence is a string that can be derived from another string by deleting some or no characters without changing the order of the remaining characters.

Constraints:

• $1 \leq$ s.length $\leq 250$

• s consists of lowercase English letters.

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