
    Write a function that checks if student-submitted variable names follow proper snake_case formatting conventions in programming assignments. The function should verify that the variable names consist only of lowercase letters connected by underscores and return true if they meet this standard, or false otherwise.
    

    
import re

def text_lowercase_underscore(text):
    """
    Write a function that checks if student-submitted variable names follow proper snake_case formatting conventions in programming assignments. The function should verify that the variable names consist only of lowercase letters connected by underscores and return true if they meet this standard, or false otherwise.
    

    """
import re

def text_lowercase_underscore(text):
    """
    Write a function that checks if student-submitted variable names follow proper snake_case formatting conventions in programming assignments. The function should verify that the variable names consist only of lowercase letters connected by underscores and return true if they meet this standard, or false otherwise.
    

    """
    patterns = '^[a-z]+_[a-z]+$'
    if re.search(patterns, text):
        return True
    else:
        return False