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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 remove(in_bam):
 """ remove bam file and the index if exists """

    if utils.file_exists(in_bam):
        utils.remove_safe(in_bam)
    if utils.file_exists(in_bam + ".bai"):
        utils.remove_safe(in_bam + ".bai")