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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 copy_cwl_files(from_dir=CWL_PATH, to_dir=None):
 """Copy cwl files to a directory where the cwl-runner can find them. Args: from_dir (str):
 Path to directory where to copy files from (default: the cwl directory of nlppln). to_dir (str):
 Path to directory where the files should be copied to (e.g., the CWL working directory). """

    cwl_files = glob.glob('{}{}*.cwl'.format(from_dir, os.sep))
    # if no files are found, the output directory should not be created
    if len(cwl_files) > 0:
        create_dirs(to_dir)
    for fi in cwl_files:
        fo = os.path.join(to_dir, os.path.basename(fi))
        shutil.copy2(fi, fo)

    return len(cwl_files)