pydoc > collections.abc.MutableMapping

📛 NAME

collections.abc.MutableMapping = class MutableMapping(Mapping)

Help on class MutableMapping in collections.abc:

🚀 Quick Reference

Use Case	Command	Description
Create a mutable mapping subclass	class MyDict(MutableMapping): ...	Override __getitem__, __setitem__, __delitem__, __len__, __iter__
Remove all items	d.clear()	D.clear() -> None. Remove all items from D.
Remove and return value for key	d.pop(key, default)	D.pop(k[,d]) -> v, remove specified key and return value. Raises KeyError if not found and no default.
Remove and return arbitrary item	d.popitem()	D.popitem() -> (k, v), remove and return a (key, value) pair; raises KeyError if empty.
Set default value for key	d.setdefault(key, default)	D.setdefault(k[,d]) -> D.get(k,d), also set D[k]=d if k not in D.
Update with another mapping/iterable	d.update(other, **kwds)	D.update([E, ]**F) -> None. Update D from mapping/iterable E and F.

📖 Description

A MutableMapping is a generic container for associating key/value pairs.

This class provides concrete generic implementations of all methods except for __getitem__, __setitem__, __delitem__, __iter__, and __len__.

🔗 Method Resolution Order

• MutableMapping
• Mapping
• Collection
• Sized
• Iterable
• Container
• builtins.object

⚙️ Methods defined here

• __delitem__(self, key)
• __setitem__(self, key, value)
• clear(self) — D.clear() -> None. Remove all items from D.
• pop(self, key, default=<object object at 0x7f8d63ba0190>) — D.pop(k[,d]) -> v, remove specified key and return the corresponding value. If key is not found, d is returned if given, otherwise KeyError is raised.
• popitem(self) — D.popitem() -> (k, v), remove and return some (key, value) pair as a 2-tuple; but raise KeyError if D is empty.
• setdefault(self, key, default=None) — D.setdefault(k[,d]) -> D.get(k,d), also set D[k]=d if k not in D
• update(self, other=(), /, **kwds) — D.update([E, ]**F) -> None. Update D from mapping/iterable E and F.

  If E present and has a .keys() method, does:     for k in E: D[k] = E[k]
  If E present and lacks .keys() method, does:     for (k, v) in E: D[k] = v
  In either case, this is followed by: for k, v in F.items(): D[k] = v

---

📦 Data and other attributes defined here

• __abstractmethods__ = frozenset({'__delitem__', '__getitem__', '__iter__', '__len__', '__setitem__'})

---

🔗 Methods inherited from Mapping

• __contains__(self, key)
• __eq__(self, other) — Return self==value.
• __getitem__(self, key)
• get(self, key, default=None) — D.get(k[,d]) -> D[k] if k in D, else d. d defaults to None.
• items(self) — D.items() -> a set-like object providing a view on D's items
• keys(self) — D.keys() -> a set-like object providing a view on D's keys
• values(self) — D.values() -> an object providing a view on D's values

---

📦 Data and other attributes inherited from Mapping

• __hash__ = None
• __reversed__ = None

---

📚 Class methods inherited from Collection

• __subclasshook__(C) from abc.ABCMeta — Abstract classes can override this to customize issubclass(). This is invoked early on by abc.ABCMeta.__subclasscheck__(). It should return True, False or NotImplemented. If it returns NotImplemented, the normal algorithm is used. Otherwise, it overrides the normal algorithm (and the outcome is cached).

---

📏 Methods inherited from Sized

• __len__(self)

---

🔄 Methods inherited from Iterable

• __iter__(self)

---

📚 Class methods inherited from Iterable

• __class_getitem__ = GenericAlias(...) from abc.ABCMeta — Represent a PEP 585 generic type. E.g. for t = list[int], t.__origin__ is list and t.__args__ is (int,).