title: ConfigParser python 2.7. Delimiter is getting changed to '=' after config write
body: <p>I have a file looks like below</p>
  
  <pre><code>[SectionOne]
  Status: Single
  Name: Derek
  Value: Yes
  Age: 30
  Single: True
  </code></pre>
  
  <p>After i read and modify a field, the delimiter is getting changed to '=' instead of ':' as below </p>
  
  <pre><code>[SectionOne]
  Status = Married
  Name = Derek
  Value = Yes
  Age = 30
  Single = True
  </code></pre>
  
  <p>I am using python 2.7 and i cannot migrate to a new version of python now.</p>
  
  <p>the code is below</p>
  
  <pre><code>Config = ConfigParser.ConfigParser()
  Config.read("Bacpypes.ini")
  cfgfile = open("Bacpypes.ini")
  Config.set('SectionOne', 'Status', 'Married')
  Config.write(cfgfile
  cfgfile.close()
  </code></pre>
  
  <p>Thanks in advance</p>