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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 create_expansions(self, environment_id, collection_id, expansions, **kwargs):
 """ Create or update expansion list. Create or replace the Expansion list for this collection. The maximum number of expanded terms per collection is `500`. The current expansion list is replaced with the uploaded content. :param str environment_id: The ID of the environment. :param str collection_id: The ID of the collection. :param list[Expansion] expansions: An array of query expansion definitions. Each object in the **expansions** array represents a term or set of terms that will be expanded into other terms. Each expansion object can be configured as bidirectional or unidirectional. Bidirectional means that all terms are expanded to all other terms in the object. Unidirectional means that a set list of terms can be expanded into a second list of terms. To create a bi-directional expansion specify an **expanded_terms** array. When found in a query, all items in the **expanded_terms** array are then expanded to the other items in the same array. To create a uni-directional expansion, specify both an array of **input_terms** and an array of **expanded_terms**. When items in the **input_terms** array are present in a query, they are expanded using the items listed in the **expanded_terms** array. :param dict headers: A `dict` containing the request headers :return: A `DetailedResponse` containing the result, headers and HTTP status code. :rtype: DetailedResponse """


        if environment_id is None:
            raise ValueError('environment_id must be provided')
        if collection_id is None:
            raise ValueError('collection_id must be provided')
        if expansions is None:
            raise ValueError('expansions must be provided')
        expansions = [self._convert_model(x, Expansion) for x in expansions]

        headers = {}
        if 'headers' in kwargs:
            headers.update(kwargs.get('headers'))
        sdk_headers = get_sdk_headers('discovery', 'V1', 'create_expansions')
        headers.update(sdk_headers)

        params = {'version': self.version}

        data = {'expansions': expansions}

        url = '/v1/environments/{0}/collections/{1}/expansions'.format(
            *self._encode_path_vars(environment_id, collection_id))
        response = self.request(
            method='POST',
            url=url,
            headers=headers,
            params=params,
            json=data,
            accept_json=True)
        return response