public ProgramFragment getFragment(String treeName, Address addr) {
		lock.acquire();
		try {
			ModuleManager m = treeMap.get(treeName);
			if (m != null) {
				return m.getFragment(addr);
			}

		}
		catch (IOException e) {
			errHandler.dbError(e);

		}
		finally {
			lock.release();
		}
		return null;
	}
Get the fragment that contains the given address within the tree
identified by the treeName.
@param treeName name of the tree
@param addr address contained within some fragment
@return fragment containing addr, or null if addr does not
exist in memory
Ghidra/Framework/SoftwareModeling/src/main/java/ghidra/program/database/module/TreeManager.java