def usage():
    """
    Print command line help
    """
    print(
        """usage : flexi_splitter -f <inputfile1[,inputfile2...,inputfileN]> -o <outputfolder> -c <configfile> [OPTIONS]
"""
        )
    print(
        """mandatory parameters : 
        -f, --fastqs   list of fastq files separated by a comma without whitespace 
        -o, --ofolder  path to the output folder. Need to be empty or if not
                       exists, flexi_splitter creates it
        -c, --config   path to the config file in yaml format

options : 
        -h, --help     print this message
        -v, --verbose  only usefull for debugging
        -m, --mismatch mismatches allowed per adaptor. By default, n-1 
                       mismatches are allowed (n = adaptor length) 
        -n, --ntuple   number of matched files. If not set, flexi_splitter try
                       to guess it from the config file
        --version      print flexi_splitter version """
        )
