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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 content_types(self):
 """ Provides access to content type management methods for content types of an environment. API reference: https://www.contentful.com/developers/docs/references/content-management-api/#/reference/content-types :return: :class:`EnvironmentContentTypesProxy <contentful_management.space_content_types_proxy.EnvironmentContentTypesProxy>` object. :rtype: contentful.space_content_types_proxy.EnvironmentContentTypesProxy Usage: <EnvironmentContentTypesProxy space_id="cfexampleapi" environment_id="master"> """


        return EnvironmentContentTypesProxy(self._client, self.space.id, self.id)