Refactor statistic page with class StatisticData

main/templates/pages/stat.html

@@ -31,6 +31,15 @@
     <li>{{error}}</li>
     {% endfor %}
   </ul>
+  {%if form.errors%}
+  <ul>
+    {% for field, errors in form.errors.items %}
+    {% for error in errors %}
+    <li>{{error}}</li>
+    {% endfor %}
+    {% endfor %}
+  </ul>
+  {%endif%}
 
 </div>
 {% endblock %}