def read_gene_cov_file(input_file):
    """Convert coverage mapping file into a dictionary data structure"""
    d = {}
    f = open(input_file, mode='rt')

    for line in f:
        words = line.strip().split('\t')
        gene, coverage = words[0], int(words[1])
        d[gene] = coverage
    f.close()
    return d