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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 _validate_condition_keys(self, field, value, error):
 """ Validates that all of the keys in one of the sets of keys are defined as keys of ``value``. """

        if 'field' in value:
            operators = self.nonscalar_conditions + self.scalar_conditions
            matches = sum(1 for k in operators if k in value)
            if matches == 0:
                error(field, 'Must contain one of {}'.format(operators))
                return False
            elif matches > 1:
                error(
                    field,
                    'Must contain no more than one of {}'.format(operators)
                )
                return False
            return True
        elif 'and' in value:
            for condition in value['and']:
                self._validate_condition_keys(field, condition, error)
        elif 'or' in value:
            for condition in value['or']:
                self._validate_condition_keys(field, condition, error)
        else:
            error(field, "Must contain field + operator keys, 'and', or 'or'.")
            return False