'Scenario: On the Certificates tab of the Instructor Dashboard,
Error message appears if no username/email is entered while clicking "Add Exception" button
Given that I am on the Certificates tab on the Instructor Dashboard
When I click on \'Add Exception\' button
AND student username/email field is empty
Then Error Message should say
\'Student username/email field is required and can not be empty. \'
\'Kindly fill in username/email and then press "Add Exception" button.\''

def test_error_on_empty_user_name(self):

    self.certificates_section.wait_for_certificate_exceptions_section()
    self.certificates_section.click_add_exception_button()
    self.assertIn('Student    username/email    field    is    required    and    can    not    be    empty.    Kindly    fill    in    username/email    and    then    press    "Add    to    Exception    List"    button.', self.certificates_section.message.text)
