old_contents: # encoding: utf-8
  from django import forms
  from django.utils.translation import ugettext_lazy as _
  
  from seahub.utils import validate_group_name
  
  class ProfileForm(forms.Form):
      nickname = forms.CharField(max_length=64, required=False)
      intro = forms.CharField(max_length=256, required=False)
  
      def clean_nickname(self):
          nickname = self.cleaned_data['nickname']
          if validate_group_name(nickname):
              return nickname
          else:
              raise forms.ValidationError(_(u'Nickname can only contain characters, numbers or underscore.'))
  
new_contents: # encoding: utf-8
  from django import forms
  from django.utils.translation import ugettext_lazy as _
  
  class ProfileForm(forms.Form):
      nickname = forms.CharField(max_length=64, required=False)
      intro = forms.CharField(max_length=256, required=False)
  
  
subject: Remove nickname checking, issue#20