'Call `confirm_email_change` and assert that the content was generated as expected
`expected_template`: The name of the template that should have been used
to generate the content
`expected_context`: The context dictionary that should have been used to
generate the content'

def check_confirm_email_change(self, expected_template, expected_context):

    response = confirm_email_change(self.request, self.key)
    self.assertEquals(mock_render_to_response(expected_template, expected_context).content, response.content)
