The first exercise at the end of the chapter is to replace

1 | ```
[i for i in range(3)] + [j for j in range(8,11)]
``` |

by a single list comprehension. In Python2, there is a nearly trivial solution:

1 | ```
[i for i in range(3)+range(8,11)]
``` |

However, this won't work in Python3, because range() is
a generator-like object rather than a list.
What the exercise seems to ask is
forming the *union* of two list
comprehensions. What one might think of first is not
valid Python3:

1 | ```
[i for i in range(3) "or in" range(8,11) ]
``` |

Unfortunately, "or in" is not an operator we can use.
Instead of trying the union idea, it's plausible to
use intersection.
The approach of *negative description* is
appropriate here. Something like:

1 | ```
[i for i in range(11) "except if in" range(4,8) ]
``` |

(Still not Python3 syntax, but turns out to be a helpful step in problem-solving.) Using a conditional list comprehension enables the idea to be expressed:

1 | ```
[i for i in range(11) if i not in range(4,8) ]
``` |