def extract_prefix(keys):
    prefixes = set()
    for key in keys:
        parts = key.split(".")
        if len(parts) > 1:
            prefixes.add(parts[0])
        else:
            return ""
    if len(prefixes) == 1:
        return prefixes.pop() + "."
    return ""
Is PL/pgSQL installed?
dataset/ETHPy150Open Sage-Bionetworks/synapsePythonClient/synapseclient/utils.py/extract_prefix--crossover with--dataset/ETHPy150Open perseas/Pyrseas/pyrseas/testutils.py/PgTestDb.is_plpgsql_installed