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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_pseudo_open(self, sel, name, has_selector, iselector, index):
 """Parse pseudo with opening bracket."""


        flags = FLG_PSEUDO | FLG_OPEN
        if name == ':not':
            flags |= FLG_NOT
        if name == ':has':
            flags |= FLG_RELATIVE

        sel.selectors.append(self.parse_selectors(iselector, index, flags))
        has_selector = True
        return has_selector