Common Python Errors and How to Fix Them
Browse all documented Python errors with detailed explanations, root causes, and step-by-step fixes.
SyntaxError: expected ':', got 'def'
This error occurs when Python expects a colon (:) but instead encounters a different keyword or token, in this case, the…
CursorError: LastError: (1062, "Duplicate entry 'user123' for key 'username'
This error occurs when trying to insert a duplicate value into a unique index in a database. In this case, the error is …
RuntimeError: cannot pickle local function '<locals>.<lambda>'
This error occurs when a function or object cannot be serialized because it is not pickleable. In this case, it is a lam…
TypeError: 'NoneType' object is not subscriptable
This error occurs when you're trying to access or manipulate a value that is currently set to 'None'. This can happen wh…
Got multiple values for key 'username' in config file
This error occurs when the configuration file or dictionary contains multiple values for the same key. In Python framewo…
TypeError: can't set attribute 'name' on weakref instance
This error occurs when you try to modify an object that has been garbage-collected or is no longer accessible, typically…
CursorObject has no attribute 'execute_many'
This error occurs when you try to use the 'execute_many' method on a cursor object that does not support it. This is typ…
CursorError: unsupported database type: 'sqlite3': 'DBM' mode not supported on t
This error occurs when trying to use the 'DBM' mode of SQLite database on a platform that does not support it. SQLite's …
SyntaxError: invalid syntax. expected ==, got =
This error occurs when Python encounters a line of code that it does not understand because of an invalid syntax.…
RuntimeError: Event loop is closed while an asynchronous task is still pending
This error occurs when a Python async function or coroutine is still running when the event loop is closed, typically wh…
RuntimeError: Thread 'Thread-1' of thread group 0x7f5a9c6b7000 finished: 'Thread
A RuntimeError is raised when the Python interpreter encounters an error that prevents it from continuing execution. Thi…
MemoryError: Unable to allocate 1000 bytes for an array with shape (1000, 1000)
The MemoryError is a runtime error that occurs when the program runs out of memory or when it is unable to allocate memo…
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