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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 detect_format(filename):
 """Detect file format of the channels based on extension. Parameters filename : Path name of the filename Returns ------- str file format """

    filename = Path(filename)

    if filename.suffix == '.csv':
        recformat = 'csv'
    elif filename.suffix == '.sfp':
        recformat = 'sfp'

    else:
        recformat = 'unknown'

    return recformat