What syntax is used to create generators in Python?

In Python, generators are created using the syntax with the keyword yield inside a function.

# Simple generator
def simple_generator():
    yield 1
    yield 2
    yield 3

# Using the generator
gen = simple_generator()
print(next(gen))  # Outputs 1
print(next(gen))  # Outputs 2
print(next(gen))  # Outputs 3
# print(next(gen))  # Raises StopIteration

# Generator expression (list comprehension-like syntax)
gen_expr = (i * 2 for i in range(5))
print(list(gen_expr))  # Outputs [0, 2, 4, 6, 8]

Table comparing a generator with a regular function returning a list:

Feature	Generator (with yield)	Regular function (returning a list)
Return value	Generator object (iterator)	List
Memory	Lazy evaluation (on demand)	All elements are created immediately
State	Preserves state between calls	Each execution starts from zero
Iteration	Iterates once	Can be iterated multiple times