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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 get_project(self, project_id):
 """ Returns a Project instance. :param project_id: Project identifier :returns: Project instance """


        try:
            UUID(project_id, version=4)
        except ValueError:
            raise aiohttp.web.HTTPBadRequest(text="Project ID {} is not a valid UUID".format(project_id))

        if project_id not in self._projects:
            raise aiohttp.web.HTTPNotFound(text="Project ID {} doesn't exist".format(project_id))
        return self._projects[project_id]