Indent comprehensions in Python

Python's comprehensions are useful, but if you try to do something a little more complicated, you end up with multi-step nesting. And nesting significantly reduces readability. For this reason, I think that many people will rewrite it in block notation when the nesting hierarchy becomes deeper.

However, if you set rules and indent, nesting will not compromise readability. For example, it looks like this:

itemList = [
    (item.name, item.price)
	for item in record.items()
    for purchase in purchases
    if purchase.campaignName in {
        campaign.name
        for campaign in camapigns
    } and purchase.date > datetime.date.today() - datetime.timedelta(days = 7)
]

Align the indentation of the parentheses on the outside of the inclusion notation, and indent one of the contents.
Divide by element, for clause, (for clause) ..., (if clause).

It may take some getting used to, but once you get used to it, it will be much easier to read than block notation. Considering that the block notation increases unnecessary variables for saving lists and reduces readability, the merit of being able to nest unlimitedly in the comprehension notation is quite large.