title: Python dataclasses: initialize and hide fields of superclass
body: <p>I would like to achieve that I can craete a sub-dataclass <code>B</code> from dataclass <code>A</code>, where <code>B</code> would initialize and thus hide fields from <code>A</code>:</p>
  <pre class="lang-py prettyprint-override"><code>@dataclass
  class A:
    a: str
    b: str
  
  @dataclass
  class B(A):
    c: str
  
    # not working! just showing, what i'd like to achive
    def __init__(self):
      self.a = f&quot;extended-{c}&quot;
  
  test = B(b=&quot;foo&quot;, c=&quot;bar&quot;)  # &lt;-- parameter 'a' should not be required and available
  
  test.a  # &quot;extended-bar&quot;
  test.b  # &quot;foo&quot;
  test.c  # &quot;bar&quot;
  </code></pre>
  <p>Is that somehow possible?</p>