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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 parse_tag_pattern(self, sel, m, has_selector):
 """Parse tag pattern from regex match."""


        parts = [css_unescape(x) for x in m.group(0).split('|')]
        if len(parts) > 1:
            prefix = parts[0]
            tag = parts[1]
        else:
            tag = parts[0]
            prefix = None
        sel.tag = ct.SelectorTag(tag, prefix)
        has_selector = True
        return has_selector