Python Exceptions

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Built-in Exceptions

AssertionError

Raised when assert statement fails

AttributeError

Raised when attribute assignment or reference fails

EOFError

Raised when the input() function hits end-of-file condition

FloatingPointError

Raised when a floating point operation fails

GeneratorExit

Raised when a generator's close() method is called

ImportError

Raised when the imported module is not found

IndexError

Raised when index of a sequence is out of range

KeyError

Raised when a key is not found in a dictionary

KeyboardInterrupt

Raised when the user hits interrupt key (CTRL+C or Delete)

MemoryError

Raised when an operation runs out of memory

NameError

Raised when a variable is not found in local or global scope

NotImplementedError

Raised by abstract methods

OverflowError

Raised when result of an arithmetic operation is too large to be represented

ReferenceError

Raised when a weak reference proxy is used to access a garbage collected referent

RuntimeError

Raised when an error does not fall under any other category

StopIteration

Raised by next() function to indicate that there is no further item to be returned by iterator

SyntaxError

Raised by parser when syntax error is encountered

IndentationError

Raised when there is incorrect indentation

TabError

Raised when indentation consists of inconsistent tabs and spaces

SystemError

Raised when interpreter detects internal error

SystemExit

Raised by sys.exit() function

TypeError

Raised when a function or operation is applied to an object of incorrect type

UnboundLocalError

Raised when a reference is made to a local variable in a function or method, but no value has been bound to that variable

ValueError

Raised when a function gets argument of correct type but improper value

ZeroDivisionError

Raised when second operand of division or modulo operation is zero

Notes