<SYSTEM_TASK:>
Solve the following problem using Python, implementing the functions described below, one line at a time
<END_TASK>
<USER_TASK:>
Description:
 def read_hlas(fasta_fai):
 """Get HLA alleles from the hg38 fasta fai file. """

    out = []
    with open(fasta_fai) as in_handle:
        for line in in_handle:
            if line.startswith("HLA"):
                out.append(line.split()[0])
    return out