removed 1st edition code

17-it-generator/tree/step0/test_tree.py

@@ -1,8 +0,0 @@
-from tree import tree
-
-
-def test_1_level():
-    class One: pass
-    expected = ['One']
-    result = list(tree(One))
-    assert expected == result 

17-it-generator/tree/step0/tree.py

@@ -1,7 +0,0 @@
-def tree(cls):
-    yield cls.__name__
-
-
-if __name__ == '__main__':
-    for cls_name in tree(BaseException):
-        print(cls_name)