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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 sys_mem_limit(self):
 """Determine the default memory limit for the current service unit."""

        if platform.machine() in ['armv7l']:
            _mem_limit = self.human_to_bytes('2700M')  # experimentally determined
        else:
            # Limit for x86 based 32bit systems
            _mem_limit = self.human_to_bytes('4G')

        return _mem_limit