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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 add_metadata(file_name, title, artist, album):
 """ As the method name suggests """

    
    tags = EasyMP3(file_name)
    if title: 
        tags["title"] = title
    if artist:     
        tags["artist"] = artist
    if album:
        tags["album"] = album
    tags.save()

    return file_name