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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 _convert_snapshots(topo_dir):
 """ Convert 1.x snapshot to the new format """

    old_snapshots_dir = os.path.join(topo_dir, "project-files", "snapshots")
    if os.path.exists(old_snapshots_dir):
        new_snapshots_dir = os.path.join(topo_dir, "snapshots")
        os.makedirs(new_snapshots_dir)

        for snapshot in os.listdir(old_snapshots_dir):
            snapshot_dir = os.path.join(old_snapshots_dir, snapshot)
            if os.path.isdir(snapshot_dir):
                is_gns3_topo = False

                # In .gns3project fileformat the .gns3 should be name project.gns3
                for file in os.listdir(snapshot_dir):
                    if file.endswith(".gns3"):
                        shutil.move(os.path.join(snapshot_dir, file), os.path.join(snapshot_dir, "project.gns3"))
                        is_gns3_topo = True

                if is_gns3_topo:
                    snapshot_arc = os.path.join(new_snapshots_dir, snapshot + ".gns3project")
                    with zipfile.ZipFile(snapshot_arc, 'w', allowZip64=True) as myzip:
                        for root, dirs, files in os.walk(snapshot_dir):
                            for file in files:
                                myzip.write(os.path.join(root, file), os.path.relpath(os.path.join(root, file), snapshot_dir), compress_type=zipfile.ZIP_DEFLATED)

        shutil.rmtree(old_snapshots_dir)