import re


def clean_text(text):
	"""
	Cleans a string from upper, special and unicode characters (ignored by double ascii conversion).
	:param text: string to clean
	:return: cleaned string
	"""
	cleaned_text = text.lower()
	for char in ["\n", "\t", "\r"]:
		cleaned_text = cleaned_text.replace(char, " ")
	cleaned_text = cleaned_text.encode("ascii", "ignore").decode("ascii")
	return re.sub(r"[^\w\s]", "", cleaned_text)