Determines whether all items in the set are present in the specified set

## Usage

The `issubset()` method returns True if all items in the set are present in the specified set, otherwise FALSE.

In set theory, every set is a subset of itself.

For example, `A.issubset(A)` is True.

## Syntax

set.issubset(set)

 Parameter Condition Description set Required A set to search for common items in

## Basic Example

Example: Check if all items in A are present in B

``````A = {'yellow', 'red'}
B = {'red', 'green', 'blue', 'yellow'}

print(A.issubset(B))	# True``````

Venn Diagram:

## Equivalent Operator <=

You can achieve the same result by using the `<=` comparison operator.

Example:

``````A = {'yellow', 'red'}
B = {'red', 'green', 'blue', 'yellow'}

print(A <= B)	# True``````

## Find Proper Subset

To test whether the set is a proper subset of other, use `<` comparison operator.

Set A is considered a proper subset of B, if A is a subset of B, but A is not equal to B.

Example: Check if A is a proper subset of B

``````A = {'yellow', 'red'}
B = {'red', 'green', 'blue', 'yellow'}

print(A < B)	# True``````
``````A = {'yellow', 'red'}
B = {'yellow', 'red'}

print(A < B)	# False``````