title: Changing a value in a yaml file using Python
body: <p>I have a <code>.yaml</code> file I want to update with Python code. Let's say it looks something like that:</p>
  <pre><code>  state: 'present'
  </code></pre>
  <p>I'd like to have a code that changes the state and saves the file. I'm trying with something like this and fail:</p>
  <pre><code>def set_state(state):
      with open(&quot;file_to_edit.yaml&quot;, 'rw') as f:
          doc = yaml.load(f)
      doc['state'] = state
      yaml.dump(f)
  </code></pre>
  <p>I am using the 'yaml' package for Python.</p>