use decode_jwt;
/**
* This function extracts the user ID from a JWT token.
* It takes a JWT token as input and returns the user ID as a string.
* If the decoding fails, it returns None.
* # Arguments
* * `jwt` - A string slice that holds the JWT token from which to extract the user ID.
* # Returns
* * `Option<String>` - An option that contains the user ID as a string if successful,
* or None if decoding fails.
*/