404 Error Passing A "Alert" Sentence From Python To Html Page, But No Error For Passing Just A Word

Update: The error message I get with the sentence is 404 Resource not found. 'GET /unexpected/The%20Notebook%20name%20is%20taken%20already HTTP/1.1' 404 - The URL looks like this

Solution 1:

My problem is that I am trying to do this in def get( without a datastore model to transfer information to the def get(. I have defined a def get( that uses a datastore model named Trans that stores such transactional information that is contained in my sentence in a variable named reason.

class Trans(db.Model):
    reason = db.StringProperty()

My model named Unexpected looks like the following.

class Unexpected(BaseHandler):

    def get(self):
    trans=Trans.get_by_key_name('reason')
    template_values = {'trans':trans}
        path = os.path.join(TEMPLATE_DIR, 'unexpected.html')
        self.response.out.write(template.render(path, template_values))

And my python codes is as follows.

reason='That Notebook name is taken already.'
    trans = Trans(key_name='reason')
    trans.reason=reason
    trans.put()
    template_values = {'trans':trans}
    path = os.path.join(TEMPLATE_DIR, 'unexpected.html')
    self.response.out.write(template.render(path, template_values))

My unexpected.html code follows.

{% extends "base.html" %}
{% block content %}
This unexpected result occurred: <emph style="font-weight: bold">{{ trans.reason }}</emph>
<br /><br />
<label>Click the "Ok" button and to go back to the previous page so you can edit your entry .
</label>
<form action="" method="post">
<input type="hidden" name="reason" value=""></input><br />
  <input type="submit" value="Ok"/>
</form>
{% endblock content %}