fix(guide): simplify directory structure

guide/english/software-engineering/design-patterns/decorator/index.md

@@ -0,0 +1,40 @@
+---
+title: Decorator
+---
+
+The decorator is a design pattern that could modify or enhance the interface of a class.
+
+## Decorator in Python3
+Here is an example of Decorator implementation in Python3.
+
+
+```python
+class MyText(object):
+    def __init__(self, text=''):
+        self.text = text
+
+    def __str__(self):
+        return 'This is {}'.format(self.text)
+
+
+class BracketDecorator(object):
+    def __init__(self, decoratee):
+        self._decoratee = decoratee
+
+    def __str__(self):
+        return '({})'.format(self._decoratee)
+
+
+class QuoteDecorator(object):
+    def __init__(self, decoratee):
+        self._decoratee = decoratee
+
+    def __str__(self):
+        return '\"{}\"'.format(self._decoratee)
+
+
+print(BracketDecorator(MyText('apple')))
+>>> (This is apple)
+print(QuoteDecorator(MyText('banana')))
+>>> "This is banana"
+```