title: Python property and Python property setters type modified
body: <p>I am a python beginner and I am stuck in @property and @property. setter decorator.
  I want to add some data to a dictionary named __content with the use of a setter.
  This is my try, but when I run this script, only the last element is added to the dictionary!
  So what am I missing here! </p>
  
  <pre><code>class Something:
      def __init__(self,elem):
          self.__content={}
  
          self.__content.update(elem)
          print type(self.__content)
  
      @property
      def content(self):
          return self.__content
  
      @content.setter
      def content(self,elem):
          self.__content.update(elem)
  </code></pre>
  
  <p>And </p>
  
  <pre><code>from transpose import Something
  c=Something(dict(one=4))
  print c.content
  c.content=dict(two=6)
  print c.content
  </code></pre>
  
  <p>The result</p>
  
  <pre><code>/usr/bin/python /home/radouani/PycharmProjects/demoPython/test.py
  &lt;type 'dict'&gt;
  {'one': 4}
  &lt;type 'dict'&gt;
  {'two': 6}
   Process finished with exit code 0
  </code></pre>
  
  <p>Another problem : I don't understand why python change the type of __content when I try to affect a tuple or integer with the use of the setter?</p>
  
  <p>Cordially</p>