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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 atlasdb_num_peers( con=None, path=None ):
 """ How many peers are there in the db? """

    with AtlasDBOpen(con=con, path=path) as dbcon:

        sql = "SELECT MAX(peer_index) FROM peers;"
        args = ()

        cur = dbcon.cursor()
        res = atlasdb_query_execute( cur, sql, args )

        ret = []
        for row in res:
            tmp = {}
            tmp.update(row)
            ret.append(tmp)

        assert len(ret) == 1

    return ret[0]['MAX(peer_index)']