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Solve the following problem using Python, implementing the functions described below, one line at a time
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Description:

def score_for_in(self, leaderboard_name, member):
        '''
        Retrieve the score for a member in the named leaderboard.

        @param leaderboard_name Name of the leaderboard.
        @param member [String] Member name.
        @return the score for a member in the leaderboard or +None+ if the member is not in the leaderboard.
        '''
        score = self.redis_connection.zscore(leaderboard_name, member)
        if score is not None:
            score = float(score)

        return score