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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 call_ext_prog(self, prog, timeout=300, stderr=True, chroot=True, runat=None):
 """Execute a command independantly of the output gathering part of sosreport. """

        return self.get_command_output(prog, timeout=timeout, stderr=stderr,
                                       chroot=chroot, runat=runat)