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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 schema_factory(schema_name, **schema_nodes):
 """Schema Validation class factory. Args: schema_name(str):
 The namespace of the schema. schema_nodes(dict):
 The attr_names / SchemaNodes mapping of schema. Returns: A Schema class. Raises: SchemaError, for bad attribute setting initialization. Examples: OrderedDict([('lat', 34.0), ('lng', 29.01)]) OrderedDict([('lat', 34.0), ('lng', 0.0)]) <RegionSchema instance, attributes:['country_code', 'keywords', 'location', 'name']> [] Traceback (most recent call last):
 schema_factory.errors.SchemaError: Missing Required Attributes: {'country_code'} Traceback (most recent call last):
 schema_factory.errors.SchemaError: Invalid Attributes RegionSchema for {'foo'}. """


    schema_dict = dict()
    schema_dict.update(schema_nodes)

    def cls_repr(self):  # pragma: no cover
        return "<{} instance at: 0x{:x}>".format(self.__class__, id(self))

    def cls_str(self):   # pragma: no cover
        return "<{} instance, attributes:{}>".format(
            self.__class__.__name__,
            self.schema_nodes
        )

    def cls_init(self, **kwargs):

        kwargs_set = set(kwargs)

        if not self.required.issubset(kwargs_set):
            raise SchemaError('Missing Required Attributes: {}'.format(
                self.required.difference(kwargs_set)
            ))

        if not set(kwargs).issubset(set(self.schema_nodes)):
            raise SchemaError('Invalid Attributes {} for {}.'.format(
                self.__class__.__name__,
                set(kwargs).difference(set(self.schema_nodes))
            ))

        for attr_name in kwargs:
            setattr(self, attr_name, kwargs[attr_name])

    def to_dict(self):
        return OrderedDict([(k, getattr(self, k)) for k in self.schema_nodes])

    schema_dict['to_dict'] = property(to_dict)
    schema_dict['__init__'] = cls_init
    schema_dict['__repr__'] = cls_repr
    schema_dict['__str__'] = cls_str

    return SchemaType('{}Schema'.format(schema_name.title()), (), schema_dict)