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Solve the following problem using Python, implementing the functions described below, one line at a time
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Description:
 def authorize(self, me, state=None, next_url=None, scope='read'):
 """Authorize a user via Micropub. Args: me (string):
 the authing user's URL. if it does not begin with https?://, http:// will be prepended. state (string, optional):
 passed through the whole auth process, useful if you want to maintain some state, e.g. the starting page to return to when auth is complete. next_url (string, optional):
 deprecated and replaced by the more general "state". still here for backward compatibility. scope (string, optional):
 a space-separated string of micropub scopes. 'read' by default. Returns: a redirect to the user's specified authorization https://indieauth.com/auth if none is provided. """

        redirect_url = flask.url_for(
            self.flask_endpoint_for_function(self._authorized_handler),
            _external=True)
        return self._start_indieauth(
            me, redirect_url, state or next_url, scope)