code help

[perfringo]

There are lot of accusations that programming sites are very hostile places. To prove that this is not the case and there are actually friendly and fun-loving people I provide following solution (with caution).

Caution: there are times when one needs 'blue-pill' which will make all problems go away. One should be aware of the toll such a pill takes. Following is for situation: 'this-is-not-homework-but-I-am-not-allowed-to-use-built-in-tools-and-there-are-some-mandatory-expressions-I-have-to-use-but-it-is-still-not-homework'. Use responsibly and avoid overdose.

Following monty-liner delivers number of days from start of year with taking account actual leap years (not imaginary ones which happen on every fourth year):

>>> date = '13.06.2019'
>>> day, month, year = (int(x) for x in date.split('.'))
>>> sum([[31, 30][i <= 6 and i % 2 == 0 or i > 7 and i % 2 != 0] if i != 2 else [28, 29][year % 4 == 0 and year % 100 != 0 or year % 400 == 0] for i in range(1 ,13)][:month-1] + [day])
164 

As one can see all the 'work' is done on one line using list comprehension, conditional expressions, some built-in functions and operators, indexing and slicing. No fancy calendar module etc. No need for data structures or subroutines (and yes, this is actual working Python code which delivers expected result)