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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 _prepare_dump_info(project_mapping, tag_name):
 """ prepare dump file info. """

    test_path = project_mapping.get("test_path") or "tests_mapping"
    pwd_dir_path = project_mapping.get("PWD") or os.getcwd()
    file_name, file_suffix = os.path.splitext(os.path.basename(test_path.rstrip("/")))
    dump_file_name = "{}.{}.json".format(file_name, tag_name)

    return pwd_dir_path, dump_file_name