Filtering a Tag Browse Tree

I am still very new to the Ignition platform so I am having difficulty in filtering a Tag Browse Tree to show only certain tags/nodes.
I have set the Root Node Path, and I have successfully filtered to the top node, however, I cannot seem to fully filter recursively. In the screenshot, I have put boxes around the tags that I want to see. I’d prefer not see anything else (although I’m fine with the containing folders).
I’ve tried several code snippets in the filterTag Extension Function but so far, I’ve only been successful in filtering to the Flow Meter level.
My current code looks like:

	from com.inductiveautomation.ignition.common.sqltags.model import TagProp
	from com.inductiveautomation.ignition.common.sqltags.model.types import TagType
	if tag.type in (TagType.Folder, TagType.UDT_INST):
		if == "Flow_":![screenshot|217x183]
			return 0
		if == "Floats":
			return 0
		return 1

However, in the Output console, I am getting the message Error loading children of node: Meta when I click on the Meta node.
The Flow Meter {n} node will have an undetermined number, whilst the sub-nodes will always contain Floats and Meta, and the tags inside will always be the same (“External Name” and “Internal Name”).
In short, I want to only see each Flow Meter {n} node and the External Name and Internal Name tags (which are inside the Meta folder).

Any thoughts on how to filter the subfolders?
Any help or guidance is greatly appreciated.