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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 _set_init_system(self, client):
 """Determine the init system of distribution."""

        if not self.init_system:
            try:
                out = ipa_utils.execute_ssh_command(
                    client,
                    'ps -p 1 -o comm='
                )
            except Exception as e:
                raise IpaDistroException(
                    'An error occurred while retrieving'
                    ' the distro init system: %s' % e
                )
            if out:
                self.init_system = out.strip()