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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 open_magnet(self):
 """Open magnet according to os."""

        if sys.platform.startswith('linux'):
            subprocess.Popen(['xdg-open', self.magnet],
                             stdout=subprocess.PIPE, stderr=subprocess.PIPE)
        elif sys.platform.startswith('win32'):
            os.startfile(self.magnet)
        elif sys.platform.startswith('cygwin'):
            os.startfile(self.magnet)
        elif sys.platform.startswith('darwin'):
            subprocess.Popen(['open', self.magnet],
                             stdout=subprocess.PIPE, stderr=subprocess.PIPE)
        else:
            subprocess.Popen(['xdg-open', self.magnet],
                             stdout=subprocess.PIPE, stderr=subprocess.PIPE)