werkzeug.routing.BuildError
werkzeug.routing.BuildError: Could not build url for endpoint 'login'. Did you mean 'index' instead?

Traceback (most recent call last)
File "/mnt/data/dan/Projects/Apps/Python3/flask_demo3/venv/lib/python3.8/site-packages/flask/app.py", line 1950, in full_dispatch_request
rv = self.dispatch_request()
File "/mnt/data/dan/Projects/Apps/Python3/flask_demo3/venv/lib/python3.8/site-packages/flask/app.py", line 1926, in dispatch_request
self.raise_routing_exception(req)
File "/mnt/data/dan/Projects/Apps/Python3/flask_demo3/venv/lib/python3.8/site-packages/flask/app.py", line 1908, in raise_routing_exception
raise request.routing_exception
File "/mnt/data/dan/Projects/Apps/Python3/flask_demo3/venv/lib/python3.8/site-packages/flask/ctx.py", line 350, in match_request
result = self.url_adapter.match(return_rule=True)
File "/mnt/data/dan/Projects/Apps/Python3/flask_demo3/venv/lib/python3.8/site-packages/werkzeug/routing.py", line 1945, in match
raise NotFound()
During handling of the above exception, another exception occurred:
File "/mnt/data/dan/Projects/Apps/Python3/flask_demo3/venv/lib/python3.8/site-packages/flask/app.py", line 2464, in __call__
return self.wsgi_app(environ, start_response)
File "/mnt/data/dan/Projects/Apps/Python3/flask_demo3/venv/lib/python3.8/site-packages/flask/app.py", line 2450, in wsgi_app
response = self.handle_exception(e)
File "/mnt/data/dan/Projects/Apps/Python3/flask_demo3/venv/lib/python3.8/site-packages/flask/app.py", line 1867, in handle_exception
reraise(exc_type, exc_value, tb)
File "/mnt/data/dan/Projects/Apps/Python3/flask_demo3/venv/lib/python3.8/site-packages/flask/_compat.py", line 39, in reraise
raise value
File "/mnt/data/dan/Projects/Apps/Python3/flask_demo3/venv/lib/python3.8/site-packages/flask/app.py", line 2447, in wsgi_app
response = self.full_dispatch_request()
File "/mnt/data/dan/Projects/Apps/Python3/flask_demo3/venv/lib/python3.8/site-packages/flask/app.py", line 1952, in full_dispatch_request
rv = self.handle_user_exception(e)
File "/mnt/data/dan/Projects/Apps/Python3/flask_demo3/venv/lib/python3.8/site-packages/flask/app.py", line 1816, in handle_user_exception
return self.handle_http_exception(e)
File "/mnt/data/dan/Projects/Apps/Python3/flask_demo3/venv/lib/python3.8/site-packages/flask/app.py", line 1744, in handle_http_exception
return handler(e)
File "/mnt/data/dan/Projects/Apps/Python3/flask_demo3/app/errors/handlers.py", line 7, in not_found_error
return render_template('errors/404.html'), 404
File "/mnt/data/dan/Projects/Apps/Python3/flask_demo3/venv/lib/python3.8/site-packages/flask/templating.py", line 137, in render_template
return _render(
File "/mnt/data/dan/Projects/Apps/Python3/flask_demo3/venv/lib/python3.8/site-packages/flask/templating.py", line 120, in _render
rv = template.render(context)
File "/mnt/data/dan/Projects/Apps/Python3/flask_demo3/venv/lib/python3.8/site-packages/jinja2/environment.py", line 1090, in render
self.environment.handle_exception()
File "/mnt/data/dan/Projects/Apps/Python3/flask_demo3/venv/lib/python3.8/site-packages/jinja2/environment.py", line 832, in handle_exception
reraise(*rewrite_traceback_stack(source=source))
File "/mnt/data/dan/Projects/Apps/Python3/flask_demo3/venv/lib/python3.8/site-packages/jinja2/_compat.py", line 28, in reraise
raise value.with_traceback(tb)
File "/mnt/data/dan/Projects/Apps/Python3/flask_demo3/app/templates/errors/404.html", line 1, in top-level template code
{% extends "base/base.html" %}
File "/mnt/data/dan/Projects/Apps/Python3/flask_demo3/app/templates/base/base.html", line 1, in top-level template code
{% extends 'bootstrap/base.html' %}
File "/mnt/data/dan/Projects/Apps/Python3/flask_demo3/venv/lib/python3.8/site-packages/flask_bootstrap/templates/bootstrap/base.html", line 1, in top-level template code
{% block doc -%}
File "/mnt/data/dan/Projects/Apps/Python3/flask_demo3/venv/lib/python3.8/site-packages/flask_bootstrap/templates/bootstrap/base.html", line 4, in block "doc"
{%- block html %}
File "/mnt/data/dan/Projects/Apps/Python3/flask_demo3/venv/lib/python3.8/site-packages/flask_bootstrap/templates/bootstrap/base.html", line 20, in block "html"
{% block body -%}
File "/mnt/data/dan/Projects/Apps/Python3/flask_demo3/venv/lib/python3.8/site-packages/flask_bootstrap/templates/bootstrap/base.html", line 21, in block "body"
{% block navbar %}
File "/mnt/data/dan/Projects/Apps/Python3/flask_demo3/app/templates/base/base.html", line 13, in block "navbar"
<a href="{{ url_for('login') }}">{{ _('Login') }}</a>
File "/mnt/data/dan/Projects/Apps/Python3/flask_demo3/venv/lib/python3.8/site-packages/flask/helpers.py", line 370, in url_for
return appctx.app.handle_url_build_error(error, endpoint, values)
File "/mnt/data/dan/Projects/Apps/Python3/flask_demo3/venv/lib/python3.8/site-packages/flask/app.py", line 2216, in handle_url_build_error
reraise(exc_type, exc_value, tb)
File "/mnt/data/dan/Projects/Apps/Python3/flask_demo3/venv/lib/python3.8/site-packages/flask/_compat.py", line 39, in reraise
    import collections.abc as collections_abc

    def reraise(tp, value, tb=None):
        if value.__traceback__ is not tb:
            raise value.with_traceback(tb)
        raise value

    implements_to_string = _identity

else:
    iterkeys = lambda d: d.iterkeys()
File "/mnt/data/dan/Projects/Apps/Python3/flask_demo3/venv/lib/python3.8/site-packages/flask/helpers.py", line 357, in url_for
rv = url_adapter.build(
File "/mnt/data/dan/Projects/Apps/Python3/flask_demo3/venv/lib/python3.8/site-packages/werkzeug/routing.py", line 2179, in build
raise BuildError(endpoint, values, method, self)
werkzeug.routing.BuildError: Could not build url for endpoint 'login'. Did you mean 'index' instead?
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