Multiple Choice
Consider the following reducer code: 1 #!/usr/bin/env python3
2 # length_reducer.py
3 """Counts the number of words with each length."""
4 import sys
5 from itertools import groupby
6 from operator import itemgetter
7
8 def tokenize_input() :
9 """Split each line of standard input into a key and a value."""
10 for line in sys.stdin:
11 yield line.strip() .split('\t')
12
13 # produce key-value pairs of word lengths and counts separated by tabs
14 for word_length, group in groupby(tokenize_input() , itemgetter(0) ) :
15 try:
16 total = sum(int(count) for word_length, count in group)
17 print(word_length + '\t' + str(total) )
18 except ValueError:
19 pass # ignore word if its count was not an integer
Which of the following statements a) , b) or c) is false?
A) Function tokenize_input is a generator function that reads and splits the key-value pairs produced by the mapper.
B) The mapper script sends its output directly to the reducer script.
C) For each line, tokenize_input strips any leading or trailing whitespace (such as the terminating newline) and yields a list containing the key and a value.
D) All of the above statements are true.
Correct Answer:

Verified
Correct Answer:
Verified
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