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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 print_serial_number_info(self, serial_number, print_to_screen=True):
 """Print information about the run. Args: serial_number: serial number. print_to_screen: runs the print statement if True, returns txt if not. Returns: txt if print_to_screen is False, else None. """

        r = self.select_serial_number_row(serial_number)
        if r.empty:
            warnings.warn("missing serial number")
            return

        txt1 = 80 * "="
        txt1 += "\n"
        txt1 += f"   serial number {serial_number}\n"
        txt1 = 80 * "-"
        txt1 += "\n"
        txt2 = ""
        for label, value in zip(r.columns, r.values[0]):
            if label in self.headers:
                txt1 += f"{label}:    \t {value}\n"
            else:
                txt2 += f"({label}:    \t {value})\n"
        if print_to_screen:
            print(txt1)
            print(80 * "-")
            print(txt2)
            print(80 * "=")
            return
        else:
            return txt1