There are some cases where it is useful to connect multiple generators into one. This allows us to delegate the operations of one generator to another sub-generator. Connecting generators is similar to using the itertools chain() function to combine iterators into a single iterator.

In order to connect generators, we use the yield from statement. An example of how it is used is below:

def cs_courses():
    yield 'Computer Science'
    yield 'Artificial Intelligence'

def art_courses():
    yield 'Intro to Art'
    yield 'Selecting Mediums'


def all_courses():
    yield from cs_courses()
    yield from art_courses()

combined_generator = all_courses()

Let’s break down this example:

• We have a generator function called cs_courses() that yields two results, 'Computer Science' and 'Artificial Intelligence'.
• We have another generator function called art_courses() that will yield two separate results, 'Intro to Art' and 'Selecting Mediums'.
• Our all_courses() generator function will yield results from both cs_courses() and art_courses() to create one combined generator with all four string values representing the courses.

If we iterate through each value within combined_generator using print() and next(), we can see that yield from retrieves each individual yield item at a time in the order that the yields are called within the generator functions.

print(next(combined_generator))
print(next(combined_generator))
print(next(combined_generator))
print(next(combined_generator))

Our printouts will look like the following:

Computer Science
Artificial Intelligence
Intro to Art
Selecting Mediums

Let’s practice more examples of how to connect generators.