Generators are mem-efficient lazy lists

[x * 2 if x % 2 == 0
    else x + 1
    for x in xrange(5, 10)]

{ key:value for item in list if conditional }


def fib(n):
    a, b = 0, 1
    for i in xrange(n):
        yield a
        a, b = b, a + b

[i for i in fib(100)]

Note: a lot of yield syntax with distinct semantics

[(i, j) for i in xrange 4  for j in xrange(3) if ....]

presentations
2018
CodingTech - A Story of Generator
    https://www.youtube.com/watch?v=WkWIGEOydkQ
CodingTech - Python Generators
    https://www.youtube.com/watch?v=XEn_99daJro