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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 train(self, cloud=None, batch=False, api_key=None, version=None, **kwargs):
 """ This is the basic training endpoint. Given an existing dataset this endpoint will train a model. Inputs api_key (optional) - String: Your API key, required only if the key has not been declared elsewhere. This allows the API to recognize a request as yours and automatically route it to the appropriate destination. cloud (optional) - String: Your private cloud domain, required only if the key has not been declared elsewhere. This allows the API to recognize a request as yours and automatically route it to the appropriate destination. """

        url_params = {"batch": batch, "api_key": api_key, "version": version, 'method': "train"}
        return self._api_handler(self.keywords['collection'], cloud=cloud, api="custom", url_params=url_params, **kwargs)