def invoke(self, ctx):
        """Given a context, this invokes the attached callback (if it exists)
        in the right way.
        """
        _maybe_show_deprecated_notice(self)
        if self.callback is not None:
            return ctx.invoke(self.callback, **ctx.params)
Given a context, this invokes the attached callback (if it exists)
        in the right way.
        
dynaconf/vendor/click/core.py