gistfile1.txt

def some_task(catalog, ...):
    ...
    data, changed = catalog.load_url(url, path)
    
    # If the data is not changed, and we are updating... we're done
    if not changed and catalog.args.update:
        return

    # Continue processing, update data blah blah blah
    ...
    return


class Catalog:

    ...
    
    def load_url(self, url, path, write=True):
        # Load cached data...
        if self.args.archive:
            data = self._load_cached_url(path)
        # Load data from url
        else:
            data = self._load_url_data(url)
    
        # Check if the data is changed
        ...     
        changed = ...
    
        # Save url data to cache
        if write:
            ...
        
        return data, changed