def build_LM(in_file):
"""
build language models for each label
each line in in_file contains a label and a string separated by a space
"""
print('building language models...')
# This is an empty method
# Pls implement your code below in
# LMs is a dict to store the LM for each language
LMs = {}
with open(in_file, 'r') as file:
for line in file:
(label, text) = line.strip("\r\n").split(" ", 1)
if label not in LMs:
LMs[label] = NgramLM(label,
gram_size=gram_size,
token_based=token_based,
start_end=start_end,
case_sensitive=case_sensitive,
strip_out=strip_out,
add_one_smoothing=add_one_smoothing)
LMs[label].train(text)
return LMs
