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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 check_backend() -> bool: """Check if gatttool is available on the system."""

        try:
            call('gatttool', stdout=PIPE, stderr=PIPE)
            return True
        except OSError as os_err:
            msg = 'gatttool not found: {}'.format(str(os_err))
            _LOGGER.error(msg)
        return False