public ProgramFragment getFragment(String treeName, String name) {
		lock.acquire();
		try {
			ModuleManager m = treeMap.get(treeName);
			if (m != null) {
				return m.getFragment(name);
			}
		}
		catch (IOException e) {
			errHandler.dbError(e);

		}
		finally {
			lock.release();
		}
		return null;
	}
Get the fragment with the given name that is in the tree identified
by the treeName.
@param treeName name of the tree
@param name name of fragment to look for
@return null if there is no fragment with the given name in the tree
Ghidra/Framework/SoftwareModeling/src/main/java/ghidra/program/database/module/TreeManager.java