Editor crashes when calling AssetTools.find_soft_references_to_object()

The following Python code crashes my Editor:

import unreal as ue

source = '/Game/Path/To/MyAsset'

at = ue.AssetToolsHelpers().get_asset_tools()
refs = at.find_soft_references_to_object(ue.SoftObjectPath(source))
ue.log(refs)

Any tips?