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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 build_filename(filename, filetype='png', resolution=300):
 """ Uses the input properties to create the string of the filename :param str filename: Name of the file :param str filetype: Type of file :param int resolution: DPI resolution of the output figure """

    filevals = os.path.splitext(filename)
    if filevals[1]:
        filetype = filevals[1][1:]
    if not filetype:
        filetype = 'png'
    filename = filevals[0] + '.' + filetype

    if not resolution:
        resolution = 300
    return filename, filetype, resolution