import re
txt = """\n\
<?php\n\
/* Multi-line\n\
comment */\n\
$var = 1;\n"""
new_txt = re.sub(r'/\*.*?\*/', '', txt, flags=re.S)
print("\n=========== TXT ============")
print(txt)
print("\n=========== NEW TXT ============")
print(new_txt)
aW1wb3J0IHJlCgp0eHQgPSAiIiJcblwKPD9waHBcblwKLyogTXVsdGktbGluZVxuXApjb21tZW50ICovXG5cCiR2YXIgPSAxO1xuIiIiCm5ld190eHQgPSByZS5zdWIocicvXCouKj9cKi8nLCAnJywgdHh0LCBmbGFncz1yZS5TKQpwcmludCgiXG49PT09PT09PT09PSBUWFQgPT09PT09PT09PT09IikKcHJpbnQodHh0KQpwcmludCgiXG49PT09PT09PT09PSBORVcgVFhUID09PT09PT09PT09PSIpCnByaW50KG5ld190eHQp