Special Methods Table

This table lists all of the special methods together with their parameter and return types. In the table below, a parameter name of self is used to indicate that the parameter has the type that the method belongs to. Other parameters with no type specified in the table are generic Python objects.

You don’t have to declare your method as taking these parameter types. If you declare different types, conversions will be performed as necessary.

General

Name	Parameters	Return type	Description
__cinit__	self, ...		Basic initialisation (no direct Python equivalent)
__init__	self, ...		Further initialisation
__dealloc__	self		Basic deallocation (no direct Python equivalent)
__cmp__	x, y	int	3-way comparison
__richcmp__	x, y, int op	object	Rich comparison (no direct Python equivalent)
__str__	self	object	str(self)
__repr__	self	object	repr(self)
__hash__	self	int	Hash function
__call__	self, ...	object	self(...)
__iter__	self	object	Return iterator for sequence
__getattr__	self, name	object	Get attribute
__getattribute__	self, name	object	Get attribute, unconditionally
__setattr__	self, name, val		Set attribute
__delattr__	self, name		Delete attribute

Arithmetic operators

Name	Parameters	Return type	Description
__add__	x, y	object	binary + operator
__sub__	x, y	object	binary - operator
__mul__	x, y	object	* operator
__div__	x, y	object	/ operator for old-style division
__floordiv__	x, y	object	// operator
__truediv__	x, y	object	/ operator for new-style division
__mod__	x, y	object	% operator
__divmod__	x, y	object	combined div and mod
__pow__	x, y, z	object	** operator or pow(x, y, z)
__neg__	self	object	unary - operator
__pos__	self	object	unary + operator
__abs__	self	object	absolute value
__nonzero__	self	int	convert to boolean
__invert__	self	object	~ operator
__lshift__	x, y	object	<< operator
__rshift__	x, y	object	>> operator
__and__	x, y	object	& operator
__or__	x, y	object	| operator
__xor__	x, y	object	^ operator

Numeric conversions

Name	Parameters	Return type	Description
__int__	self	object	Convert to integer
__long__	self	object	Convert to long integer
__float__	self	object	Convert to float
__oct__	self	object	Convert to octal
__hex__	self	object	Convert to hexadecimal
__index__ (2.5+ only)	self	object	Convert to sequence index

In-place arithmetic operators

Name	Parameters	Return type	Description
__iadd__	self, x	object	+= operator
__isub__	self, x	object	-= operator
__imul__	self, x	object	*= operator
__idiv__	self, x	object	/= operator for old-style division
__ifloordiv__	self, x	object	//= operator
__itruediv__	self, x	object	/= operator for new-style division
__imod__	self, x	object	%= operator
__ipow__	x, y, z	object	**= operator
__ilshift__	self, x	object	<<= operator
__irshift__	self, x	object	>>= operator
__iand__	self, x	object	&= operator
__ior__	self, x	object	|= operator
__ixor__	self, x	object	^= operator

Sequences and mappings

Name	Parameters	Return type	Description
__len__	self int		len(self)
__getitem__	self, x	object	self[x]
__setitem__	self, x, y		self[x] = y
__delitem__	self, x		del self[x]
__getslice__	self, Py_ssize_t i, Py_ssize_t j	object	self[i:j]
__setslice__	self, Py_ssize_t i, Py_ssize_t j, x		self[i:j] = x
__delslice__	self, Py_ssize_t i, Py_ssize_t j		del self[i:j]
__contains__	self, x	int	x in self

Iterators

Name	Parameters	Return type	Description
__next__	self	object	Get next item (called next in Python)

Buffer interface

Note

The buffer interface is intended for use by C code and is not directly accessible from Python. It is described in the Python/C API Reference Manual under sections 6.6 and 10.6.

Name	Parameters	Return type	Description
__getreadbuffer__	self, int i, void **p
__getwritebuffer__	self, int i, void **p
__getsegcount__	self, int *p
__getcharbuffer__	self, int i, char **p

Descriptor objects

Note

Descriptor objects are part of the support mechanism for new-style Python classes. See the discussion of descriptors in the Python documentation. See also PEP 252, “Making Types Look More Like Classes”, and PEP 253, “Subtyping Built-In Types”.

Name	Parameters	Return type	Description
__get__	self, instance, class	object	Get value of attribute
__set__	self, instance, value		Set value of attribute
__delete__	self, instance		Delete attribute