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Solve the following problem using Python, implementing the functions described below, one line at a time
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Description:
 def _escapeCharacters(tag):
 	"""non-recursively escape underlines and asterisks 	in the tag"""

	for i,c in enumerate(tag.contents):
		if type(c) != bs4.element.NavigableString:
			continue
		c.replace_with(_escapeCharSub(r'\\\1', c))