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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 namedb_get_account(cur, address, token_type):
 """ Get an account, given the address. Returns the account row on success Returns None if not found """

    sql = 'SELECT * FROM accounts WHERE address = ? AND type = ? ORDER BY block_id DESC, vtxindex DESC LIMIT 1;'
    args = (address,token_type)

    rows = namedb_query_execute(cur, sql, args)
    row = rows.fetchone()
    if row is None:
        return None

    ret = {}
    ret.update(row)
    return ret