title: local variable referenced before assignment django error
body: <p>This is my view.py and when i have a form which when i submit with the required fields it gives an appropriate output but when i don't input anything in the form and click submit i get an error saying "local variable 'researcher' referenced before assignment".</p>
  
  <p>Also i want to know how do i keep my form data saved on the destination page</p>
  
  <pre><code>def about_experiment(request,ex_link_name):
  
      if request.method == 'POST':
          form = AboutHelp(request.POST)
          if form.is_valid():
              researcher = form.cleaned_data['researcher']
              study = form.cleaned_data['study']
  
      else:
          form = AboutHelp()
      return render(request, 'about_experiment.html', {'researcher': researcher, 'study': study})
  </code></pre>
  
  <p>my form on the source page is </p>
  
  <pre><code>&lt;form action="{% url 'lazer.views.about_experiment' exp.link_name %}" method="POST" name="form"&gt; 
    {% csrf_token %}
        &lt;label&gt;Researcher Name(s):&lt;input type="text" name="researcher"&gt;
      &lt;lable&gt;Study Summary&lt;textarea rows="10" cols="50" placeholder="here you go" maxlength="500" class="form-control" name="study"&gt;&lt;/textarea&gt;
        &lt;br&gt;
        &lt;input type = "submit" value="Submit" class="btn btn-primary" /&gt;
    &lt;/form&gt;
  </code></pre>
  
  <p>My destination page where the form outputs are present</p>
  
  <pre><code>&lt;h4&gt; Name : {{ researcher }} &lt;/h4&gt;&lt;br&gt;
  &lt;h4&gt; Summary : {{ study }} &lt;/h4&gt;
  </code></pre>