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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 drop_alembic_version_table():
 """Drop alembic_version table."""

    if _db.engine.dialect.has_table(_db.engine, 'alembic_version'):
        alembic_version = _db.Table('alembic_version', _db.metadata,
                                    autoload_with=_db.engine)
        alembic_version.drop(bind=_db.engine)