Answers for "pytube.exceptions.RegexMatchError: get_throttling_function_name: could not find match for multiple"

pytube.exceptions.RegexMatchError: get_throttling_function_name: could not find match for multiple

Becuase youtube changed something on its end, and now you have to change pytube's ciper.py's function_patterns to the following
line: 272 ~ 273
r'a\.[a-zA-Z]\s*&&\s*\([a-z]\s*=\s*a\.get\("n"\)\)\s*&&\s*'
r'\([a-z]\s*=\s*([a-zA-Z0-9$]{2,3})(\[\d+\])?\([a-z]\)'

line: 288

nfunc=re.escape(function_match.group(1))),

RegexMatchError: get_throttling_function_name: could not find match for multiple pytube

try upgrading pytube like this:
pip install pytube --upgrade