Error Types
These are the most common built in exceptions in Python.
| ERROR | EXPLANATION |
|---|---|
ValueError | Raised when a function receives an argument of the right type but an inappropriate value. |
TypeError | Raised when an operation or function is applied to an object of inappropriate type. |
FileNotFoundError | Raised when trying to open a file that does not exist. |
IndexError | Raised when trying to access an element from a list or tuple with an invalid index. |
KeyError | Raised when trying to access a dictionary with a key that does not exist. |
AttributeError | Raised when an attribute reference or assignment fails. |
ImportError | Raised when an import statement fails to find the module definition or when a from ... import fails. |
ModuleNotFoundError | Raised when a module could not be found. |
ZeroDivisionError | Raised when attempting to divide by zero. |
NameError | Raised when a local or global name is not found. |
UnboundLocalError | Raised when trying to access a local variable before it has been assigned. |
SyntaxError | Raised when the parser encounters a syntax error. |
IndentationError | Raised when there is an incorrect indentation. |
TabError | Raised when mixing tabs and spaces in indentation. |
IOError | Raised when an I/O operation (such as a print statement or the open() function) fails. |
OSError | Raised when a system-related operation causes an error. |
StopIteration | Raised to signal the end of an iterator. |
RuntimeError | Raised when an error is detected that doesn't fall in any of the other categories. |
RecursionError | Raised when the maximum recursion depth is exceeded. |
NotImplementedError | Raised by abstract methods that need to be implemented by subclasses. |
AssertionError | Raised when an assert statement fails. |
FloatingPointError | Raised when a floating point operation fails. |
OverflowError | Raised when the result of an arithmetic operation is too large to be expressed. |
MemoryError | Raised when an operation runs out of memory. |
EOFError | Raised when the input() function hits an end-of-file condition. |
KeyboardInterrupt | Raised when the user hits the interrupt key (usually Ctrl+C or Delete). |
ConnectionError | Base class for network-related errors. |
TimeoutError | Raised when a system function times out. |
BrokenPipeError | Raised when a pipe is broken during a write operation. |
IsADirectoryError | Raised when a file operation (such as open()) is attempted on a directory. |
PermissionError | Raised when trying to perform an operation without the necessary permissions. |
ChildProcessError | Raised when a child process operation fails. |
BlockingIOError | Raised when an operation would block on an object (like a socket) set for non-blocking mode. |
SystemExit | Raised by the sys.exit() function. |
GeneratorExit | Raised when a generator’s close() method is called. |