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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 clear(self):
 """ Clear the terminal screen. """

        if hasattr(self.stdout, 'isatty') and self.stdout.isatty() or self.term_type == 'mintty':
            cmd, shell = {
                'posix': ('clear', False),
                'nt': ('cls', True),
                'cygwin': (['echo', '-en', r'\ec'], False),
                'mintty': (r'echo -en "\ec', False),
            }[self.term_type]
            subprocess.call(cmd, shell=shell, stdin=self.stdin, stdout=self.stdout, stderr=self.stderr)