Write a function to find sequences of lowercase letters joined with an underscore.
import re
def text_lowercase_underscore(text):
        patterns = '^[a-z]+_[a-z]+$'
        if re.search(patterns,  text):
                return 'Found a match!'
        else:
                return('Not matched!')
<s>[INST]<<SYS>>Given a task and its code, generate test cases for the code.<</SYS>>Write a function to find sequences of lowercase letters joined with an underscore.
import re
def text_lowercase_underscore(text):
        patterns = '^[a-z]+_[a-z]+$'
        if re.search(patterns,  text):
                return 'Found a match!'
        else:
                return('Not matched!')[/INST]assert text_lowercase_underscore("aab_cbbbc")==('Found a match!')
assert text_lowercase_underscore("aab_Abbbc")==('Not matched!')
assert text_lowercase_underscore("Aaab_abbbc")==('Not matched!')</s>