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Set

Set is a container compatible with the built-in set, which serializes values and stores them in a sqlite3 database.

Set[T](...)

Constructor.

Type Parameters:

  • T: value type

Arguments:

  • data: Iterable[T], optional, positional-only argument, defualt=None; Initial data. If None or no argument is given, persistent data is used as is if available, otherwise persistent data in the corresponding table is cleared and given data is stored instead.
  • connection: str or sqlite3.Connection, optional, default=None; If None, temporary file is automatically created. If connection is a str, it will be used as the sqlite3 database file name. You can pass a sqlite3.Connection directly.
  • table_name: str, optional, default=None; Table name of this container. If None, an auto-generated unique name will be used. Available characters are letters, numbers, and underscores (_).
  • serializer: Callable[[T], bytes], optional, default=None; Function to serialize value. If None, pickle.dumps is used.
  • deserializer: Callable[[bytes], T], optional, default=None; Function to deserialize value. If None, pickle.loads is used.
  • persist: bool, optional, default=True; If True, table won't be deleted even when the object is deleted. If False, the table is deleted when this object is deleted.
  • pickling_strategy: PicklingStrategy, optional, default=PicklingStrategy.whole_table; Flag to control pickling method. See PicklingStrategy for more details.

len(s)

Return the number of items in s: Set[T]

Return value:

int: The number of items in s

x in s

True if x is in s, else False

Arguments:

  • x: object; an object to be checked

Return value:

bool: True if x is in s and False otherwise.

x not in s

False if x is in s, else True

Arguments:

  • x: object; an object to be checked

Return value:

bool: False if x is in s and True otherwise.

isdisjoint(other)

Return True if the set has no elements in common with other.

Arguments:

  • other: Iterable[T]; Iterable to check if disjoint.

Return value:

bool: True if the set is disjoint with other, False otherwise.

issubset(other)

Return True if every element in the set is in other.

Arguments:

  • other: Iterable[T]; Iterable to check if this one contains the set.

Return value:

bool: True if the set is subset of other, False otherwise.

s <= other

Return True if every element in the set is in other.

Argument:

  • other : Iterable[T]; Iterable to check if this one contains all the elements in the set.

Return value:

bool: True if the set is subset of other, False otherwise.

s < other

Return True if every element in the set is in other and s is not equal to other.

Arguments:

  • other: Iterable[T]; Iterable to check if it contains all elements of the set and is not equal to the set.

Return value:

bool: True if the set is a proper subset of other, False otherwise.

issuperset(other)

Return True if every element in other is in the set.

Arguments:

  • other: Iterable[T]; Iterable to check if the elements are contained.

Return value:

bool: True if the set is superset of other, False otherwise.

s >= other

Return True if every element in other is in the set.

Argument:

  • other: Iterable[T]; Iterable to check if the elements are contained.

Return value:

bool: True if the set is superset of other, False otherwise.

s > other

Return True if every element in other is in the set and s is not equal to other.

Arguments:

  • other: Iterable[T]; Iterable to check if it all elements are in the set and is not equal to the set.

Return value:

bool: True if the set is a proper superset of other, False otherwise.

union(*others)

Return a new set with elements from the set and all others.

Arguments:

  • others: Iterable[T]; Iterables to take the union.

Return value:

Set[T]: A new set with elements from the set and all others.

s | other

Return a new set with elements from s and other.

Arguments:

  • other: Iterable[T]; Iterable to take the union.

Return value:

Set[T]: A new set with elements from s and other.

intersection(*others)

Return a new set with elements common to the set and all others.

Arguments:

  • others: Iterable[T]; Iterables to take the intersection.

Return value:

Set[T]: A new set with elements common to the set and all others.

s & other

Return a new set with elements common to s and other.

Arguments:

  • other: Iterable[T]; Iterable to take the intersection.

Return value:

Set[T]: A new set with elements common to s and other.

difference(*others)

Return a new set with elements in the set that are not in the others.

Arguments:

  • others: Iterable[T]; Iterables to take the difference.

Return value:

Set[T]: A new set with elements in the set that are not in the others.

s - other

Return a new set with elements in the set that are not in the other.

Arguments:

  • other: Iterable[T]; Iterable to take the difference.

Return value:

Set[T]: A new set with elements in the set that are not in the other.

symmetric_difference(other)

Return a new set with elements in either the set or other but not both.

Arguments:

  • other: Iterable[T]; Iterable to take the symmetric difference.

Return value:

Set[T]: A new set with elements in either the set or other but not both.

s ^ other

Return a new set with elements in either the set or other but not both.

Arguments:

  • other: Iterable[T]; Iterable to take the symmetric difference.

Return value:

Set[T]: A new set with elements in either the set or other but not both.

copy()

Return a copy of the set. The actual behavior is to create a table with a unique table name and copy the elements to the new table. Therefore, unlike the built-in set copy, the behavior is similar to deep copy. Be aware that the copied set is volatile.

Return value:

Set[T]: A volatile copy of the set.

update(*others)

Update the set by adding elements from all others.

Arguments:

  • others: Iterable[T]; Iterables to take the union.

Return value:

None.

s |= other

Update the set by adding elements from other.

Arguments:

  • other: Iterable[T]; Iterable to take the union.

Return value:

None.

intersection_update(*others)

Update the set by keeping only elements found in the set and all others.

Arguments:

  • others: Iterable[T]; Iterables to take the intersection.

Return value:

None.

s &= other

Update the set by keeping only elements found in the set and other.

Arguments:

  • other: Iterable[T]; Iterable to take the intersection.

Return value:

None.

symmetric_difference_update(other)

Update the set by keeping only elements found in either the set or other but not both.

Arguments:

  • other: Iterable[T]; Iterable to take the symmetric difference.

Return value:

None.

s ^= other

Update the set by keeping only elements found in either the set or other but not both.

Arguments:

  • other: Iterable[T]; Iterable to take the symmetric difference.

Return value:

None.

add(elem)

Add an element elem to the set.

Arguments:

  • elem: T; An element to be added.

Return value:

None.

remove(elem)

Remove an element elem from the set. Raises KeyError if elem is not contained in the set.

Arguemnts:

  • elem: T; An element to be removed.

Return value:

None.

discard(elem)

Remove an element elem from the set if it is present.

Arguments:

  • elem: T; An element to be removed.

Return value:

None.

pop()

Remove and return an arbitrary element from the set. Raises KeyError if the set is empty.

Return value:

T: An element in the set.

clear()

Remove all elements from the set.

Return value:

None.