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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_file_list(shortFile):
 """ The function get_file_list expands a short filename to a sorted list of filenames. The short filename can contain variables and wildcards. """

    if "://" in shortFile: # seems to be a URL
        return [shortFile]

    # expand tilde and variables
    expandedFile = os.path.expandvars(os.path.expanduser(shortFile))

    # expand wildcards
    fileList = glob.glob(expandedFile)

    # sort alphabetical,
    # if list is emtpy, sorting returns None, so better do not sort
    if len(fileList) != 0:
        fileList.sort()
    else:
        logging.warning("No file matches '%s'.", shortFile)

    return fileList