Asked about Generators and working with large data
Can you call len() on a generator?
An answer that works
No. A generator does not know how many items it will produce and cannot look ahead. If you need a count, either convert it to a list or count as you iterate.
Reading an answer is not being able to give one. The section that teaches this is Generators and working with large data, 3 hours of Python.
Learn this properlyAlso asked about Python
What is the difference between a list and a tuple?Why use join instead of adding strings in a loop?What is the difference between == and is?What does s[::-1] do?How would you remove duplicates from a list?Why is checking membership in a set faster than in a list?What happens if you use a list as a dictionary key?What is the difference between sorted(x) and x.sort()?
All 36 questions on Python