@Override
	public void deleteAddressRange(Address startAddr, Address endAddr, TaskMonitor monitor)
			throws CancelledException {
		lock.acquire();
		try {
			// Remove functions which overlap deleted address range
			Iterator<Function> iter = getFunctionsOverlapping(new AddressSet(startAddr, endAddr));
			while (iter.hasNext()) {
				monitor.checkCancelled();
				FunctionDB func = (FunctionDB) iter.next();
				removeFunction(func.getEntryPoint());
			}
		}
		finally {
			lock.release();
		}
	}
Get the function with the given key.
@param key ID of the function; ID is obtained by calling
Function.getID()
@return null if there is no function with the given key
Ghidra/Framework/SoftwareModeling/src/main/java/ghidra/program/database/function/FunctionManagerDB.java