→ abc/

abc/abcmeta.py

@@ -0,0 +1,49 @@
+from __future__ import division, print_function
+import abc
+
+
+class Base(object):
+    __metaclass__ = abc.ABCMeta
+
+    @abc.abstractproperty
+    def x(self):
+        return 'Should never get here'
+
+    @abc.abstractmethod
+    def process(self, data):
+        """ Process data.
+        Return bool
+
+        """
+        return
+
+    def __del__(self):
+        print("__del__")
+
+
+class Implementation(Base):
+    def __init__(self):
+        self._x = True
+
+    @property
+    def x(self):
+        return self._x
+
+    @x.setter
+    def x(self, value):
+        self._x = value
+
+    def process(self, data):
+        data += 1
+        return True
+
+# b = Base()
+# print(b.x)
+
+i = Implementation()
+print(i.x)
+a = 1
+i.process(a)
+print(a)
+
+i2 = Implementation()