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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 cross_dir(self, forcex86=False):
 r""" Cross platform specific subfolder. Parameters forcex86: bool Use 'x86' as current architecture even if current acritecture is not x86. Return ------ subfolder: str '' if target architecture is current architecture, '\current_target' if not. """

        current = 'x86' if forcex86 else self.current_cpu
        return (
            '' if self.target_cpu == current else
            self.target_dir().replace('\\', '\\%s_' % current)
        )