Check out example codes for "pokemon go". It will help you in understanding the concepts better.

Code Example 1

>>> a = set([1, 2, 3, 4])
>>> b = set([3, 4, 5, 6])
>>> a | b # Union
{1, 2, 3, 4, 5, 6}
>>> a & b # Intersection
{3, 4}
>>> a < b # Subset
False
>>> a - b # Difference
{1, 2}
>>> a ^ b # Symmetric Difference
{1, 2, 5, 6}

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