SqlAlchemy Event Exception

SqlAlchemyexception

Traceback (most recent call last):
  File "/usr/local/lib/python2.7/dist-packages/flask/app.py", line 1836, in __call__
    return self.wsgi_app(environ, start_response)
  File "/usr/local/lib/python2.7/dist-packages/flask/app.py", line 1820, in wsgi_app
    response = self.make_response(self.handle_exception(e))
  File "/usr/local/lib/python2.7/dist-packages/flask/app.py", line 1403, in handle_exception
    reraise(exc_type, exc_value, tb)
  File "/usr/local/lib/python2.7/dist-packages/flask/app.py", line 1817, in wsgi_app
    response = self.full_dispatch_request()
  File "/usr/local/lib/python2.7/dist-packages/flask/app.py", line 1477, in full_dispatch_request
    rv = self.handle_user_exception(e)
  File "/usr/local/lib/python2.7/dist-packages/flask/app.py", line 1381, in handle_user_exception
    reraise(exc_type, exc_value, tb)
  File "/usr/local/lib/python2.7/dist-packages/flask/app.py", line 1475, in full_dispatch_request
    rv = self.dispatch_request()
  File "/usr/local/lib/python2.7/dist-packages/flask_debugtoolbar/__init__.py", line 125, in dispatch_request
    return view_func(**req.view_args)
  File "/usr/lib/python2.7/cProfile.py", line 149, in runcall
    return func(*args, **kw)
  File "/usr/local/lib/python2.7/dist-packages/flask_superadmin/base.py", line 37, in inner
    return f(self, *args, **kwargs)
  File "/usr/local/lib/python2.7/dist-packages/flask_superadmin/base.py", line 37, in inner
    return f(self, *args, **kwargs)
  File "/usr/local/lib/python2.7/dist-packages/flask_superadmin/base.py", line 37, in inner
    return f(self, *args, **kwargs)
  File "/usr/local/lib/python2.7/dist-packages/flask_superadmin/base.py", line 37, in inner
    return f(self, *args, **kwargs)
  File "/usr/local/lib/python2.7/dist-packages/flask_superadmin/model/base.py", line 345, in edit
    pk=self.get_pk(instance), instance=instance)
  File "/usr/local/lib/python2.7/dist-packages/flask_superadmin/base.py", line 169, in render
    return render_template(template, **kwargs)
  File "/usr/local/lib/python2.7/dist-packages/flask/templating.py", line 128, in render_template
    context, ctx.app)
  File "/usr/local/lib/python2.7/dist-packages/flask/templating.py", line 110, in _render
    rv = template.render(context)
  File "/usr/share/pyshared/jinja2/environment.py", line 969, in render
    return self.environment.handle_exception(exc_info, True)
  File "/usr/share/pyshared/jinja2/environment.py", line 742, in handle_exception
    reraise(exc_type, exc_value, tb)
  File "/usr/local/lib/python2.7/dist-packages/flask_superadmin/templates/admin/model/edit.html", line 3, in top-level template code
    {% set name = admin_view.get_display_name() %}
  File "/usr/local/lib/python2.7/dist-packages/flask_superadmin/templates/admin/layout.html", line 21, in top-level template code
    {% block page_body %}
  File "/usr/local/lib/python2.7/dist-packages/flask_superadmin/templates/admin/layout.html", line 70, in block "page_body"
    {% block body %}{% endblock %}
  File "/usr/local/lib/python2.7/dist-packages/flask_superadmin/templates/admin/model/edit.html", line 26, in block "body"
    {{ lib.render_form(form, extra(), admin_view.can_edit, admin_view.can_delete) }}
  File "/usr/local/lib/python2.7/dist-packages/flask_superadmin/templates/admin/_macros.html", line 192, in template
    {{ render_formfield(form) }}
  File "/usr/local/lib/python2.7/dist-packages/flask_superadmin/templates/admin/_macros.html", line 180, in template
    {{ render_ff(form._fields[field_name]) }}
  File "/usr/local/lib/python2.7/dist-packages/flask_superadmin/templates/admin/_macros.html", line 142, in template
    {{ ff(class=class) }}
  File "/usr/local/lib/python2.7/dist-packages/wtforms/fields/core.py", line 139, in __call__
    return self.widget(self, **kwargs)
  File "/usr/local/lib/python2.7/dist-packages/flask_superadmin/form.py", line 96, in __call__
    return super(ChosenSelectWidget, self).__call__(field, **kwargs)
  File "/usr/local/lib/python2.7/dist-packages/wtforms/widgets/core.py", line 243, in __call__
    for val, label, selected in field.iter_choices():
  File "/usr/local/lib/python2.7/dist-packages/wtforms/ext/sqlalchemy/fields.py", line 108, in iter_choices
    for pk, obj in self._get_object_list():
  File "/usr/local/lib/python2.7/dist-packages/wtforms/ext/sqlalchemy/fields.py", line 101, in _get_object_list
    self._object_list = list((text_type(get_pk(obj)), obj) for obj in query)
  File "/usr/local/lib/python2.7/dist-packages/sqlalchemy/orm/query.py", line 2404, in __iter__
    return self._execute_and_instances(context)
  File "/usr/local/lib/python2.7/dist-packages/sqlalchemy/orm/query.py", line 2417, in _execute_and_instances
    close_with_result=True)
  File "/usr/local/lib/python2.7/dist-packages/sqlalchemy/orm/query.py", line 2408, in _connection_from_session
    **kw)
  File "/usr/local/lib/python2.7/dist-packages/sqlalchemy/orm/session.py", line 843, in connection
    close_with_result=close_with_result)
  File "/usr/local/lib/python2.7/dist-packages/sqlalchemy/orm/session.py", line 847, in _connection_for_bind
    return self.transaction._connection_for_bind(engine)
  File "/usr/local/lib/python2.7/dist-packages/sqlalchemy/orm/session.py", line 298, in _connection_for_bind
    self._assert_active()
  File "/usr/local/lib/python2.7/dist-packages/sqlalchemy/orm/session.py", line 192, in _assert_active
    "This session is in 'committed' state; no further "
InvalidRequestError: This session is in 'committed' state; no further SQL can be emitted within this transaction.