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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 broadcast_url(self, broadcast_id=None, stop=False, layout=False):
 """ this method returns urls for working with broadcast """

        url = self.api_url + '/v2/project/' + self.api_key + '/broadcast'

        if broadcast_id:
            url = url + '/' + broadcast_id
        if stop:
            url = url + '/stop'
        if layout:
            url = url + '/layout'
        return url