def putChild(self, path, child):
        """
        Register a static child.

        You almost certainly don't want '/' in your path. If you
        intended to have the root of a folder, e.g. /foo/, you want
        path to be ''.

        @param path: A single path component.
        @type path: L{bytes}

        @param child: The child resource to register.
        @type child: L{IResource}

        @see: L{IResource.putChild}
        """
        if not isinstance(path, bytes):
            warnings.warn(
                'Path segment must be bytes; '
                'passing {0} has never worked, and '
                'will raise an exception in the future.'
                .format(type(path)),
                category=DeprecationWarning,
                stacklevel=2)

        self.children[path] = child
        child.server = self.server

        Register a static child.

        You almost certainly don't want '/' in your path. If you
        intended to have the root of a folder, e.g. /foo/, you want
        path to be ''.

        @param path: A single path component.
        @type path: L{bytes}

        @param child: The child resource to register.
        @type child: L{IResource}

        @see: L{IResource.putChild}
        
stackoverflow/venv/lib/python3.6/site-packages/twisted/web/resource.py