title: Flask form doesn' allow î and ô
body: <p>I have a Flask Form which display a list of categories fetched from a database. The option list contains 2 words which make the form crash : "hôtel" and "gîte", containing a "^" : The form send me back an error : "ascii". But words like "établissement" work. </p>
  
  <p>In other part of the form I have human input data, which can get some "î" or"ô" without raising exceptions.</p>
  
  <p>Here is the form edition : </p>
  
  <pre><code>class EditStep1Form(Form):
  """Step 1 place creation / edit form"""
  
  
  category_id = OptGroupSelectField(
      _(u'type de lieu'),
      [wtf.validators.NumberRange(
          min=1,
          message=_(u"Veuillez renseigner la catégorie"))],
      coerce=int, id='cat-id')
  name = wtf.TextField(
      _(u'nom *'),
      [wtf.validators.Required(
          message=_(u"Veuillez renseigner le nom du lieu")),
       wtf.validators.Length(
           min=1, message=_(u"Le nom du lieu est trop court"))],
      id='nom')
  </code></pre>
  
  <p>The categorie's display is about text, while the validation is about category_id, ie number.</p>
  
  <p>Here is the category retrieval function : I noticed there is no encoding on the category.</p>
  
  <pre><code>def _placeform_category_choices(lang='fr'):
      """Return categories grouped by category group"""
  
      groups = models.CategoryGroup._fetch_all(g.db.session, is_activated=True)
      cats_dict = collections.defaultdict(list)
      for group in groups:
          cats_dict[group.any_name(lang=lang)] = \
              [c for c in group.categories if c.is_activated]
      cats_list = sorted([(gp, cats) for gp, cats in cats_dict.items()],
                         key=lambda t: len(t[1]))
  
      # category choices
      category_choices = [
          (cat_gp, [(c.id, c.any_name(lang=lang)) for c in cats])
          for cat_gp, cats in cats_list]
  
      first_choices = category_choices[0][1]
      category_choices[0] = cats_list[0][0], [(-1, '---')] + first_choices
  
      return category_choices
  </code></pre>
  
  <p>Why should WTF allow to display "î" but wouldn't recognise it while validating the form ? (I suspected a bug on the "id number" and the "text", but this bug doesn't raise if there is no "î" like in "café").</p>
  
  <p>Why does it raises a "ascii" errors only for "î" and "ô" while "é" and "è" are not ascii anyway ?? </p>