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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 _load_submissions_from_datastore_dir(self, dir_suffix, id_pattern):
 """Loads list of submissions from the directory. Args: dir_suffix: suffix of the directory where submissions are stored, one of the folowing constants: ATTACK_SUBDIR, TARGETED_ATTACK_SUBDIR or DEFENSE_SUBDIR. id_pattern: pattern which is used to generate (internal) IDs for submissins. One of the following constants: ATTACK_ID_PATTERN, TARGETED_ATTACK_ID_PATTERN or DEFENSE_ID_PATTERN. Returns: dictionary with all found submissions """

    submissions = self._storage_client.list_blobs(
        prefix=os.path.join(self._round_name, dir_suffix))
    return {
        id_pattern.format(idx): SubmissionDescriptor(
            path=s, participant_id=participant_from_submission_path(s))
        for idx, s in enumerate(submissions)
    }