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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 _compile_dict(self, schema):
 """Validate a dictionary. A dictionary schema can contain a set of values, or at most one validator function/type. A dictionary schema will only validate a dictionary: An invalid dictionary value: An invalid key: Validation function, in this case the "int" type: Valid integer input: {10: 'twenty'} By default, a "type" in the schema (in this case "int") will be used purely to validate that the corresponding value is of that type. It will not Coerce the value: Wrap them in the Coerce() function to achieve this: {10: 'twenty'} Custom message for required key (This is to avoid unexpected surprises.) Multiple errors for nested field in a dict: ["expected int for dictionary value @ data['adict']['intfield']", "expected str for dictionary value @ data['adict']['strfield']"] """

        base_validate = self._compile_mapping(
            schema, invalid_msg='dictionary value')

        groups_of_exclusion = {}
        groups_of_inclusion = {}
        for node in schema:
            if isinstance(node, Exclusive):
                g = groups_of_exclusion.setdefault(node.group_of_exclusion, [])
                g.append(node)
            elif isinstance(node, Inclusive):
                g = groups_of_inclusion.setdefault(node.group_of_inclusion, [])
                g.append(node)

        def validate_dict(path, data):
            if not isinstance(data, dict):
                raise er.DictInvalid('expected a dictionary', path)

            errors = []
            for label, group in groups_of_exclusion.items():
                exists = False
                for exclusive in group:
                    if exclusive.schema in data:
                        if exists:
                            msg = exclusive.msg if hasattr(exclusive, 'msg') and exclusive.msg else \
                                "two or more values in the same group of exclusion '%s'" % label
                            next_path = path + [VirtualPathComponent(label)]
                            errors.append(er.ExclusiveInvalid(msg, next_path))
                            break
                        exists = True

            if errors:
                raise er.MultipleInvalid(errors)

            for label, group in groups_of_inclusion.items():
                included = [node.schema in data for node in group]
                if any(included) and not all(included):
                    msg = "some but not all values in the same group of inclusion '%s'" % label
                    for g in group:
                        if hasattr(g, 'msg') and g.msg:
                            msg = g.msg
                            break
                    next_path = path + [VirtualPathComponent(label)]
                    errors.append(er.InclusiveInvalid(msg, next_path))
                    break

            if errors:
                raise er.MultipleInvalid(errors)

            out = data.__class__()
            return base_validate(path, iteritems(data), out)

        return validate_dict