    def test_command_downloadS3_relative_path(self):
        """
        target: test command 'downloadS3' relative path
        method: use downloadS3 to download files in S3 relative path without bucket_name
        expected: download successfully
        """
        if os.path.exists("./test.pt"):
            os.system("rm test.pt")
        res = os.popen("towhee downloadS3 -pl ./ -pb test/test.pt").read()
        assert "success" in res
        if os.path.exists("./test.pt"):
            os.system("rm test.pt")
            return True
        else:
            return False
target: test command 'downloadS3' relative path
method: use downloadS3 to download files in S3 relative path without bucket_name
expected: download successfully
tests/testcases/test_command.py