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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 create_folder_structure(project_name, batch_name):
 """This function creates a folder structure for the batch project. The folder structure consists of main working folder ``project_name` located in the ``outdatadir`` (as defined in the cellpy configuration file) with a sub-folder named ``batch_name``. It also creates a folder inside the ``batch_name`` folder for storing the raw data. If the folders does not exist, they will be made. The function also returns the name of the info-df. Args: project_name: name of the project batch_name: name of the batch Returns: (info_file, (project_dir, batch_dir, raw_dir)) """

    out_data_dir = prms.Paths["outdatadir"]
    project_dir = os.path.join(out_data_dir, project_name)
    batch_dir = os.path.join(project_dir, batch_name)
    raw_dir = os.path.join(batch_dir, "raw_data")

    # create folders
    if not os.path.isdir(project_dir):
        os.mkdir(project_dir)
    if not os.path.isdir(batch_dir):
        os.mkdir(batch_dir)
    if not os.path.isdir(raw_dir):
        os.mkdir(raw_dir)

    # create file-name for the info_df (json)
    info_file = "cellpy_batch_%s.json" % batch_name
    info_file = os.path.join(project_dir, info_file)
    return info_file, (project_dir, batch_dir, raw_dir)