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Solve the following problem using Python, implementing the functions described below, one line at a time
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Description:
 def _improve_class_docs(app, cls, lines):
 """Improve the documentation of a class."""

    if issubclass(cls, models.Model):
        _add_model_fields_as_params(app, cls, lines)
    elif issubclass(cls, forms.Form):
        _add_form_fields(cls, lines)