baker.py

#!/usr/bin/env python
import re

output = []

# use a "with" block to automatically close I/O streams
with open('mylist.txt') as word_list:

    # read the contents of mylist.txt into the words list using list comprehension
    words = [word.strip().lower() for word in word_list]

with open('stuff.tsv') as tsv:
    # read the contents of stuff.tsv into the line list using list comprehension
    lines = [line for line in tsv]

# create a dictionary of compiled regular expressions for the word list
regexen = {}

for word in words:
    regexen[word] = re.compile(r'\b{0}\b'.format(word))

# iterate over the lines
for line in lines:

    # iterate over the word list
    for word in words:

        # create a regular expression using word boundaries around our word
        match = regexen[word].search(line.lower())

        # if we find one of the words in the line, then add it to the output list
        if match:

            # add the line to the output list
            if line.endswith('\n'):
                output.append(line)
            else:
                output.append('{0}\n'.format(line))

            # write some debug output to the console
            print('Found line {0} that matched word {1}'.format(line, word))

            # exit the word while loop
            break

# open output.tsv using a with block with write permissions
with open('output.tsv', 'w') as output_file:

    # write the output list to the file
    output_file.writelines(output)