def get_prefix_from_line(line):
    """ 
    From a bowtie1 output tsv file, return the prefix of the UMI associated with the read. 
    RELIES HEAVILY ON THE READ NAME STRUCTURE AND LINE 
    ie. K00180:778:HYGGKBBXX:4:1101:17797:37607_GAATACCCAG#19,
    
    hsa-miR-95-3p MIMAT0000094 Homo sapiens miR-95-3p       +       K00180:778:HYGGKBBXX:4:1101:17797:37607_GAATACCCAG#19   2       TTCAACGGGTATTTATTGAGCA  IIIIIIIIIIIIIIIIIIIIII  66
    """
    return line.split('\t')[2].split('_')[1][:2]