# Buggy code
def render_task_status(tasklist):
    # helper function to apply localize status information in tasklist entries
    renderedtasklist = list()

    for task in tasklist:
        if task["user"] == current_user.nickname or current_user.role_admin():
            if task["formStarttime"]:
                task["starttime"] = format_datetime(
                    task["formStarttime"], format="short", locale=web.get_locale()
                )
                task["formStarttime"] = ""
            else:
                if "starttime" not in task:
                    task["starttime"] = ""

            # localize the task status
            if isinstance(task["stat"], int):
                if task["stat"] == worker.STAT_WAITING:
                    task["status"] = _("Waiting")
                elif task["stat"] == worker.STAT_FAIL:
                    task["status"] = _("Failed")
                elif task["stat"] == worker.STAT_STARTED:
                    task["status"] = _("Started")
                elif task["stat"] == worker.STAT_FINISH_SUCCESS:
                    task["status"] = _("Finished")
                else:
                    task["status"] = _("Unknown Status")

            # localize the task type
            if isinstance(task["taskType"], int):
                if task["taskType"] == worker.TASK_EMAIL:
                    task["taskMessage"] = _("E-mail: ") + task["taskMess"]
                elif task["taskType"] == worker.TASK_CONVERT:
                    task["taskMessage"] = _("Convert: ") + task["taskMess"]
                elif task["taskType"] == worker.TASK_UPLOAD:
                    task["taskMessage"] = _("Upload: ") + task["taskMess"]
                elif task["taskType"] == worker.TASK_CONVERT_ANY:
                    task["taskMessage"] = _("Convert: ") + task["taskMess"]
                else:
                    task["taskMessage"] = _("Unknown Task: ") + task["taskMess"]

            renderedtasklist.append(task)

    return renderedtasklist


# Traceback (OperationalError)
ERROR:cps.web:Exception on /book/125 [GET]
Traceback (most recent call last):
File "/Users/jgillman/Code/calibre-web/vendor/flask/app.py", line 1817, in wsgi_app
response = self.full_dispatch_request()
File "/Users/jgillman/Code/calibre-web/vendor/flask/app.py", line 1477, in full_dispatch_request
rv = self.handle_user_exception(e)
File "/Users/jgillman/Code/calibre-web/vendor/flask/app.py", line 1381, in handle_user_exception
reraise(exc_type, exc_value, tb)
File "/Users/jgillman/Code/calibre-web/vendor/flask/app.py", line 1475, in full_dispatch_request
rv = self.dispatch_request()
File "/Users/jgillman/Code/calibre-web/vendor/flask/app.py", line 1461, in dispatch_request
return self.view_functions[rule.endpoint](**req.view_args)
File "/Users/jgillman/Code/calibre-web/vendor/flask_login.py", line 717, in decorated_view
return func(*args, **kwargs)
File "/Users/jgillman/Code/calibre-web/cps/web.py", line 381, in show_book
return render_template('detail.html', entry=entries,  cc=cc, title=entries.title, books_shelfs=book_in_shelfs)
File "/Users/jgillman/Code/calibre-web/vendor/flask/templating.py", line 128, in render_template
context, ctx.app)
File "/Users/jgillman/Code/calibre-web/vendor/flask/templating.py", line 110, in _render
rv = template.render(context)
File "/Users/jgillman/Code/calibre-web/vendor/jinja2/environment.py", line 969, in render
return self.environment.handle_exception(exc_info, True)
File "/Users/jgillman/Code/calibre-web/vendor/jinja2/environment.py", line 742, in handle_exception
reraise(exc_type, exc_value, tb)
File "/Users/jgillman/Code/calibre-web/cps/templates/detail.html", line 1, in top-level template code
{% extends "layout.html" %}
File "/Users/jgillman/Code/calibre-web/cps/templates/layout.html", line 136, in top-level template code
{% block body %}{% endblock %}
File "/Users/jgillman/Code/calibre-web/cps/templates/detail.html", line 66, in block "body"
{% if entry['custom_column_' ~ c.id]|length > 0 %}
File "/Users/jgillman/Code/calibre-web/vendor/jinja2/environment.py", line 387, in getitem
return getattr(obj, attr)
File "/Users/jgillman/Code/calibre-web/vendor/sqlalchemy/orm/attributes.py", line 316, in __get__
return self.impl.get(instance_state(instance), dict_)
File "/Users/jgillman/Code/calibre-web/vendor/sqlalchemy/orm/attributes.py", line 613, in get
value = self.callable_(state, passive)
File "/Users/jgillman/Code/calibre-web/vendor/sqlalchemy/orm/strategies.py", line 524, in _load_for_state
return self._emit_lazyload(session, state, ident_key, passive)
File "/Users/jgillman/Code/calibre-web/vendor/sqlalchemy/orm/strategies.py", line 585, in _emit_lazyload
result = q.all()
File "/Users/jgillman/Code/calibre-web/vendor/sqlalchemy/orm/query.py", line 2241, in all
return list(self)
File "/Users/jgillman/Code/calibre-web/vendor/sqlalchemy/orm/query.py", line 2353, in __iter__
return self._execute_and_instances(context)
File "/Users/jgillman/Code/calibre-web/vendor/sqlalchemy/orm/query.py", line 2368, in _execute_and_instances
result = conn.execute(querycontext.statement, self._params)
File "/Users/jgillman/Code/calibre-web/vendor/sqlalchemy/engine/base.py", line 662, in execute
params)
File "/Users/jgillman/Code/calibre-web/vendor/sqlalchemy/engine/base.py", line 761, in _execute_clauseelement
compiled_sql, distilled_params
File "/Users/jgillman/Code/calibre-web/vendor/sqlalchemy/engine/base.py", line 874, in _execute_context
context)
File "/Users/jgillman/Code/calibre-web/vendor/sqlalchemy/engine/base.py", line 1024, in _handle_dbapi_exception
exc_info
File "/Users/jgillman/Code/calibre-web/vendor/sqlalchemy/util/compat.py", line 196, in raise_from_cause
reraise(type(exception), exception, tb=exc_tb)
File "/Users/jgillman/Code/calibre-web/vendor/sqlalchemy/engine/base.py", line 867, in _execute_context
context)
File "/Users/jgillman/Code/calibre-web/vendor/sqlalchemy/engine/default.py", line 324, in do_execute
cursor.execute(statement, parameters)
OperationalError: (OperationalError) no such table: books_custom_column_1_link u'SELECT custom_column_1.id AS custom_column_1_id, custom_column_1.value AS custom_column_1_value \
nFROM custom_column_1, books_custom_column_1_link \nWHERE ? = books_custom_column_1_link.book AND custom_column_1.id = books_custom_column_1_link.value' (125,)
ERROR:tornado.access:500 GET /book/125 (::1) 89.60ms

# Fixed code
def render_task_status(tasklist):
    # helper function to apply localize status information in tasklist entries
    renderedtasklist = list()
    # task2 = task
    for task in tasklist:
        if task["user"] == current_user.nickname or current_user.role_admin():
            # task2 = copy.deepcopy(task) # = task
            if task["formStarttime"]:
                task["starttime"] = format_datetime(
                    task["formStarttime"], format="short", locale=web.get_locale()
                )
            # task2['formStarttime'] = ""
            else:
                if "starttime" not in task:
                    task["starttime"] = ""

            # localize the task status
            if isinstance(task["stat"], int):
                if task["stat"] == worker.STAT_WAITING:
                    task["status"] = _("Waiting")
                elif task["stat"] == worker.STAT_FAIL:
                    task["status"] = _("Failed")
                elif task["stat"] == worker.STAT_STARTED:
                    task["status"] = _("Started")
                elif task["stat"] == worker.STAT_FINISH_SUCCESS:
                    task["status"] = _("Finished")
                else:
                    task["status"] = _("Unknown Status")

            # localize the task type
            if isinstance(task["taskType"], int):
                if task["taskType"] == worker.TASK_EMAIL:
                    task["taskMessage"] = _("E-mail: ") + task["taskMess"]
                elif task["taskType"] == worker.TASK_CONVERT:
                    task["taskMessage"] = _("Convert: ") + task["taskMess"]
                elif task["taskType"] == worker.TASK_UPLOAD:
                    task["taskMessage"] = _("Upload: ") + task["taskMess"]
                elif task["taskType"] == worker.TASK_CONVERT_ANY:
                    task["taskMessage"] = _("Convert: ") + task["taskMess"]
                else:
                    task["taskMessage"] = _("Unknown Task: ") + task["taskMess"]

            renderedtasklist.append(task)

    return renderedtasklist