title: integer validation in django not working
body: <p>forms.py</p>
  
  <pre><code>class UserCreateProfileForm(forms.ModelForm):
      fields = ['phone_daytime', 'phone_mobile']
  
      def clean(self):
          cd=self.cleaned_data
          validate_integer(cd.get('phone_daytime', None))
          validate_integer(cd.get('phone_mobile', None))
          return cd
  
       def validate_integer(phone_daytime,phone_mobile):
      try:
          int(phone_daytime,phone_mobile)
      except (ValueError, TypeError):
          raise ValidationError('Phone number must be number')
  </code></pre>
  
  <p>I want to validate the form with two phone number field.</p>
  
  <p>The above one is not working,not throwing any error but not functioning.</p>
  
  <p>The field should not accept alphabet,special character and blank also allowed.How to do this validation.</p>
  
  <p>Thanks</p>