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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 _filter_seqs(fn):
 """Convert names of sequences to unique ids"""

    out_file = op.splitext(fn)[0] + "_unique.fa"
    idx = 0
    if not file_exists(out_file):
        with open(out_file, 'w') as out_handle:
            with open(fn) as in_handle:
                for line in in_handle:
                    if line.startswith("@") or line.startswith(">"):
                        fixed_name = _make_unique(line.strip(), idx)
                        seq = in_handle.next().strip()
                        counts = _get_freq(fixed_name)
                        if len(seq) < 26 and (counts > 1 or counts == 0):
                            idx += 1
                            print(fixed_name, file=out_handle, end="\n")
                            print(seq, file=out_handle, end="\n")
                        if line.startswith("@"):
                            in_handle.next()
                            in_handle.next()
    return out_file