def FastaIterator(handle, alphabet=single_letter_alphabet, title2ids=None):
    """Generator function to iterate over Fasta records (as SeqRecord objects).
handle - input file
alphabet - optional alphabet
title2ids - A function that, when given the title of the FASTA
file (without the beginning >), will return the id, name and
description (in that order) for the record as a tuple of strings.
If this is not given, then the entire title line will be used
as the description, and the first word as the id and name.
Note that use of title2ids matches that of Bio.Fasta.SequenceParser
but the defaults are slightly different.
"""
while True:
    line = handle.readline()
if line == '':
    return
if line[0] == '>':
    break
while True:
    if line[0] != '>':
        raise ValueError(
            "Records in Fasta files should start with '>' character")
if title2ids:
    id, name, descr = title2ids(line[1:].rstrip())
else:
    descr = line[1:].rstrip()
id = descr.split()[0]
name = id
lines = []
line = handle.readline()
while True:
    if not line:
        break
if line[0] == '>':
    break
lines.append(line.rstrip().replace(' ', '').replace('\r', ''))
line = handle.readline()
yield SeqRecord(Seq(''.join(lines), alphabet), id=id, name=name,
    description=descr)
if not line:
    return
assert False, 'Should not reach this line'
Как я могу использовать readline(), чтобы начать со второй строки?