title: Django, form is_valid() is always false
body: <p>I'm learning Django and have some troubles with forms. I try to create a simple form where I type a name and show it on another page. But is_valid() always returns false. Please, help me to find my error</p>
  
  <p><strong>forms.py</strong></p>
  
  <pre><code>from django import forms
  
  class OrderForm(forms.Form):
      user=forms.CharField(max_length=100)
  </code></pre>
  
  <p><strong>views.py</strong></p>
  
  <pre><code>def order(request):
      return render(request, 'myapp/order.html', {})
  
  
  def contact(request):
      username='not logged'
  
      if request.method == 'POST' :
          form=OrderForm(request.POST)
  
          if form.is_valid():
              username=form.cleaned_data['username']
          else:
              username='not worked'
      else:
          form=OrderForm()
  
      return render(request, 'myapp/contacts.html', {'username':username})
  </code></pre>
  
  <p><strong>order.html</strong></p>
  
  <pre><code>&lt;form name = "form" action = "{% url 'contact' %}" method = "POST" &gt;
      {% csrf_token %}
          &lt;input type="text" name="username" placeholder="Name"&gt;
          &lt;button type="submit"&gt;Login&lt;/button&gt;
  &lt;/form&gt;
  </code></pre>
  
  <p><strong>contacts.html</strong></p>
  
  <pre><code>You are : &lt;strong&gt;{{ username }}&lt;/strong&gt;
  </code></pre>