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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 get_logger(process_name, append_to_console=None, redirect_stdstream=None):
 """ method returns initiated logger"""

    if append_to_console is None:
        append_to_console = settings.settings['under_test']
    if redirect_stdstream is None:
        redirect_stdstream=not settings.settings['under_test']

    if process_name not in logger_pool:
        file_name = get_log_filename(process_name)
        log_tag = get_log_tag(process_name)
        logger_pool[process_name] = Logger(file_name, log_tag,
                                           append_to_console=append_to_console,
                                           redirect_stdstream=redirect_stdstream)
    return logger_pool[process_name].get_logger()