revert export behavior and fix test cases

conda/cli/main_list.py

@@ -217,8 +217,7 @@ def execute(args, parser):
     if args.canonical:
         format = 'canonical'
     elif args.export:
-        print_explicit(prefix, args.md5)
-        return
+        format = 'export'
     else:
         format = 'human'
 

tests/test_export.py

@@ -27,34 +27,6 @@ def test_basic(self):
             output2, error= run_command(Commands.LIST, prefix2, "-e")
             self.assertEqual(output, output2)
 
-    def test_multi_channel_export(self):
-        """
-            When try to import from txt
-            every package should come from same channel
-        """
-        with make_temp_env("python=3") as prefix:
-            assert exists(join(prefix, PYTHON_BINARY))
-            assert_package_is_installed(prefix, 'python-3')
-
-            run_command(Commands.INSTALL, prefix, "six", "-c", "conda-forge")
-            assert_package_is_installed(prefix, "six")
-
-            output, error = run_command(Commands.LIST, prefix, "-e")
-            self.assertIn("conda-forge", output)
-
-            with tempfile.NamedTemporaryFile(mode="w", suffix="txt", delete=False) as env_txt:
-                env_txt.write(output)
-                env_txt.flush()
-                env_txt.close()
-                prefix2 = make_temp_prefix()
-                run_command(Commands.CREATE, prefix2, "--file " + env_txt.name)
-
-                assert_package_is_installed(prefix2, "python")
-                assert_package_is_installed(prefix2, "six")
-
-            output2, _ = run_command(Commands.LIST, prefix2, "-e")
-            self.assertEqual(output, output2)
-
     def test_multi_channel_explicit(self):
         """
             When try to import from txt