def METHOD_NAME(self):
    """Checks that sha256 verification is happening.
    """
    # Create some sample data.
    url = "http://127.0.0.1/example.zip"
    data, _ = self._create_sample_zip()
    self._url_contents[url] = data
    sha256 = "0" * 64
    # Call the module under test.
    errors = self._call_main(expect_success=False,
                             package_name="some_name",
                             urls=[url], sha256=sha256)
    self.assertIn("Checksum mismatch", errors)