# Python set union

The Python union function combines all the items in the original set, and the specified one, and the syntax of it is

`set.union(set1, set2,…,setN)`

## Python set union example

In this example, we declared two sets, and then we combined those two using the union method.

```x = {'a', 'b', 'c', 'd'}
y = {'e', 'f', 'g', 'h'}

print('Items in x = ', x)
print('Items in y = ', y)

z = x.union(y)

print('Items in z = ', z)```
``````Items in x =  {'c', 'd', 'b', 'a'}
Items in y =  {'f', 'h', 'e', 'g'}
Items in z =  {'f', 'h', 'd', 'g', 'c', 'b', 'a', 'e'}``````

The sets don’t allow duplicate values inside them. So, using the union method to combine the two, removes those duplicate values. If you observe the output, a and c was returned only once (though they are available in both x and y).

TIP: Please refer to the set in Programming.

```x = {'a', 'b', 'c', 'd'}
y = {'a', 'f', 'g', 'c', 'h', 'j', 'k'}

print('x = ', x)
print('y = ', y)

z = x.union(y)

print('z = ', z)```
``````x =  {'b', 'a', 'c', 'd'}
y =  {'k', 'j', 'g', 'a', 'c', 'h', 'f'}
z =  {'b', 'k', 'a', 'd', 'j', 'g', 'c', 'h', 'f'}``````

## Python set union function Example 2

Let me use three of them with the union function. This example combines all three sets. It first combines items in x and then y and z.

```x = {'a', 'b' }
y = {'e', 'f', 'g', 'h'}
z = {'apple', 'cherry', 'kiwi'}

print('Items in x = ', x)
print('Items in y = ', y)
print('Items in z = ', z)

new = x.union(y, z)

print('Items in new = ', new)```
``````Items in x =  {'a', 'b'}
Items in y =  {'h', 'g', 'e', 'f'}
Items in z =  {'kiwi', 'apple', 'cherry'}
Items in new =  {'kiwi', 'g', 'h', 'apple', 'e', 'a', 'f', 'b', 'cherry'}
``````

This example shows how to combine numeric and strings.

```x = {'a', 'b' }
y = {10, 20, 30, 40}

print('Items in x = ', x)
print('Items in y = ', y)

z = x.union(y)

print('Items in z = ', z)```

Combine numeric and string output

``````Items in x =  {'b', 'a'}
Items in y =  {40, 10, 20, 30}
Items in z =  {20, 'b', 40, 10, 30, 'a'}``````

Here, we declare a numeric, string, and mixed set. Next, we used the method to combine them all and return a new one.

```x = {'a', 'b' }
y = {10, 20, 30, 40}
z = {120, 'cherry', 90, 'kiwi'}

print('Set Items in x = ', x)
print('Set Items in y = ', y)
print('Set Items in z = ', z)

new_set = x.union(y, z)

print('Set Items in new = ', new_set)```