<SYSTEM_TASK:>
Solve the following problem using Python, implementing the functions described below, one line at a time
<END_TASK>
<USER_TASK:>
Description:
 def all(self, page=1, per_page=10):
 """ Get a single page from the list of all collections. :param page [integer]: Page number to retrieve. (Optional; default: 1) :param per_page [integer]: Number of items per page. (Optional; default: 10) :return: [Array]: A single page of the Collection list. """

        url = "/collections"
        result = self._all(url, page=page, per_page=per_page)
        return CollectionModel.parse_list(result)