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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 check_required_fields(self, ignore_fields=list(), allow_no_resources=False):
 # type: (List[str], bool) -> None """Check that metadata for dataset and its resources is complete. The parameter ignore_fields should be set if required to any fields that should be ignored for the particular operation. Args: ignore_fields (List[str]):
 Fields to ignore. Default is []. allow_no_resources (bool):
 Whether to allow no resources. Defaults to False. Returns: None """

        if self.is_requestable():
            self._check_required_fields('dataset-requestable', ignore_fields)
        else:
            self._check_required_fields('dataset', ignore_fields)
            if len(self.resources) == 0 and not allow_no_resources:
                raise HDXError('There are no resources! Please add at least one resource!')
            for resource in self.resources:
                ignore_fields = ['package_id']
                resource.check_required_fields(ignore_fields=ignore_fields)