[format.python] initial formatting of the python code

This patch was generated by black [1]::

    make format.python

[1] https://github.com/psf/black

Signed-off-by: Markus Heiser <markus.heiser@darmarit.de>

tests/unit/test_answerers.py

@@ -7,7 +7,6 @@ from tests import SearxTestCase
 
 
 class AnswererTest(SearxTestCase):
-
     def test_unicode_input(self):
         query = Mock()
         unicode_payload = 'árvíztűrő tükörfúrógép'