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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(self, node):
 """ Validate DjangoQL AST tree vs. current schema """

        assert isinstance(node, Node)
        if isinstance(node.operator, Logical):
            self.validate(node.left)
            self.validate(node.right)
            return
        assert isinstance(node.left, Name)
        assert isinstance(node.operator, Comparison)
        assert isinstance(node.right, (Const, List))

        # Check that field and value types are compatible
        field = self.resolve_name(node.left)
        value = node.right.value
        if field is None:
            if value is not None:
                raise DjangoQLSchemaError(
                    'Related model %s can be compared to None only, but not to '
                    '%s' % (node.left.value, type(value).__name__)
                )
        else:
            values = value if isinstance(node.right, List) else [value]
            for v in values:
                field.validate(v)