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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 run_aggregation_by_slug(request, slug):
 """Run Aggregation By Slug"""

    sa = get_object_or_404(Aggregation, slug=slug)
    sa.execute_now = True
    sa.save()
    messages.success(request, _("Saved aggregation executed."))
    return HttpResponseRedirect(
        reverse(
            'djmongo_browse_saved_aggregations_w_params',
            args=(
                sa.database_name,
                sa.collection_name)))