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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 remove_reserved_keys(self, op):
 """ Remove reserved keywords from an op dict, which can then safely be passed into the db. Returns a new op dict, and the reserved fields """

        sanitized = {}
        reserved = {}
        
        for k in op.keys():
            if str(k) not in RESERVED_KEYS:
                sanitized[str(k)] = copy.deepcopy(op[k])
            else:
                reserved[str(k)] = copy.deepcopy(op[k])
                
        return sanitized, reserved