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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_url(self, client_id, redirect_uri, scope, state=None):
 """Get the authorization URL for your application, given the application's client_id, redirect_uri, scope, and optional state data."""

        params = [
            ('client_id', client_id),
            ('redirect_uri', redirect_uri),
            ('scope', scope)
        ]
        if state:
            params.append(('state', state))
        return "%s?%s" % (CreateSend.oauth_uri, urlencode(params))