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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 visit_regex(self, node, regex):
 """Return a ``Regex`` expression."""

        tilde, literal, flags, _ = regex
        flags = flags.text.upper()
        pattern = literal.literal  # Pull the string back out of the Literal
                                   # object.
        return Regex(pattern, ignore_case='I' in flags,
                              locale='L' in flags,
                              multiline='M' in flags,
                              dot_all='S' in flags,
                              unicode='U' in flags,
                              verbose='X' in flags,
                              ascii='A' in flags)