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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 ls(manager: Manager, offset: Optional[int], limit: Optional[int]):
 """List edges."""

    q = manager.session.query(Edge)

    if offset:
        q = q.offset(offset)

    if limit > 0:
        q = q.limit(limit)

    for e in q:
        click.echo(e.bel)