Remove duplicated packages
diff --git a/tests/requirements_txt_fixer_test.py b/tests/requirements_txt_fixer_test.py
index b725afa..c400be1 100644
--- a/tests/requirements_txt_fixer_test.py
+++ b/tests/requirements_txt_fixer_test.py
@@ -68,6 +68,12 @@
             b'f<=2\n'
             b'g<2\n',
         ),
+        (b'a==1\nb==1\na==1\n', FAIL, b'a==1\nb==1\n'),
+        (
+            b'a==1\nb==1\n#comment about a\na==1\n',
+            FAIL,
+            b'#comment about a\na==1\nb==1\n',
+        ),
         (b'ocflib\nDjango\nPyMySQL\n', FAIL, b'Django\nocflib\nPyMySQL\n'),
         (
             b'-e git+ssh://git_url@tag#egg=ocflib\nDjango\nPyMySQL\n',