Python: How to loop through blocks of lines

Question

How to go through blocks of lines separated by an empty line? The file looks like the following:

ID: 1
Name: X
FamilyN: Y
Age: 20

ID: 2
Name: H
FamilyN: F
A         


        

Answer 1

import itertools

# Assuming input in file input.txt
data = open('input.txt').readlines()

records = (lines for valid, lines in itertools.groupby(data, lambda l : l != '\n') if valid)    
output = [tuple(field.split(':')[1].strip() for field in itertools.islice(record, 1, None)) for record in records]

# You can change output to generator by    
output = (tuple(field.split(':')[1].strip() for field in itertools.islice(record, 1, None)) for record in records)

# output = [('X', 'Y', '20'), ('H', 'F', '23'), ('S', 'Y', '13'), ('M', 'Z', '25')]    
#You can iterate and change the order of elements in the way you want    
# [(elem[1], elem[0], elem[2]) for elem in output] as required in your output