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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_string(self):
 """Tokenize a Fortran string."""

        word = ''

        if self.prior_delim:
            delim = self.prior_delim
            self.prior_delim = None
        else:
            delim = self.char
            word += self.char
            self.update_chars()

        while True:
            if self.char == delim:
                # Check for escaped delimiters
                self.update_chars()
                if self.char == delim:
                    word += 2 * delim
                    self.update_chars()
                else:
                    word += delim
                    break
            elif self.char == '\n':
                self.prior_delim = delim
                break
            else:
                word += self.char
                self.update_chars()

        return word