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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 _init_jobs_table():
 """Initialise the "jobs" table in the db."""

    _jobs_table = sqlalchemy.Table(
        'jobs', _METADATA,
        sqlalchemy.Column('job_id', sqlalchemy.UnicodeText, primary_key=True),
        sqlalchemy.Column('job_type', sqlalchemy.UnicodeText),
        sqlalchemy.Column('status', sqlalchemy.UnicodeText, index=True),
        sqlalchemy.Column('data', sqlalchemy.UnicodeText),
        sqlalchemy.Column('error', sqlalchemy.UnicodeText),
        sqlalchemy.Column('requested_timestamp', sqlalchemy.DateTime),
        sqlalchemy.Column('finished_timestamp', sqlalchemy.DateTime),
        sqlalchemy.Column('sent_data', sqlalchemy.UnicodeText),
        # Callback URL:
        sqlalchemy.Column('result_url', sqlalchemy.UnicodeText),
        # CKAN API key:
        sqlalchemy.Column('api_key', sqlalchemy.UnicodeText),
        # Key to administer job:
        sqlalchemy.Column('job_key', sqlalchemy.UnicodeText),
        )
    return _jobs_table