Injects ``closure()`` into ``name`` parameters in routes.

        This sets up dependency injection for parameters named ``name``.
        When a route is invoked that has a parameter ``name``, then
        ``closure()`` is passed as that parameter's value.

        (The closure indirection is so the caller can control the time
        of construction for objects. For example, you may want to check
        the health of a database connection.)

        :param str name: Parameter name.
        :param function closure: A function with no parameters.
        :rtype: :class:`WebBuilder`

def inject(self, name, closure):
        '''Injects ``closure()`` into ``name`` parameters in routes.

        This sets up dependency injection for parameters named ``name``.
        When a route is invoked that has a parameter ``name``, then
        ``closure()`` is passed as that parameter's value.

        (The closure indirection is so the caller can control the time
        of construction for objects. For example, you may want to check
        the health of a database connection.)

        :param str name: Parameter name.
        :param function closure: A function with no parameters.
        :rtype: :class:`WebBuilder`
        '''
        self.app.install(create_injector(name, closure))
        return self