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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 _get_metadata(job_id):
 """Return any metadata for the given job_id from the metadata table."""

    # Avoid SQLAlchemy "Unicode type received non-unicode bind param value"
    # warnings.
    job_id = unicode(job_id)

    results = ENGINE.execute(
        METADATA_TABLE.select().where(
            METADATA_TABLE.c.job_id == job_id)).fetchall()
    metadata = {}
    for row in results:
        value = row['value']
        if row['type'] == 'json':
            value = json.loads(value)
        metadata[row['key']] = value
    return metadata