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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 init(self, back=None):
        '''
        Initialize the backend, only do so if the fs supports an init function
        '''
        back = self.backends(back)
        for fsb in back:
            fstr = '{0}.init'.format(fsb)
            if fstr in self.servers:
                self.servers[fstr]()