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Code review pass over the profasta library addressing correctness issues, misleading APIs, inaccurate documentation, and a memory inefficiency.

parser.py

• @classmethod signatures: AbstractHeaderParser.parse and AbstractHeaderWriter.write Protocol stubs used self instead of cls
• Parameter naming: register_writer(name, parser) and get_writer(parser_name) used parser/parser_name — renamed to writer/writer_name
• Module docstring: UniprotWriter and UniprotLikeWriter were listed as "Parser for …" — corrected to "Writer for …"
• DefaultParser docstring: claimed header_fields["description"] "might be an empty string"; the key is actually absent when there is no description

io.py

• Memory inefficiency: parse_fasta called file_object.read() upfront, loading the entire file before yielding anything — replaced with a line-by-line streaming implementation:

# Before — reads whole file into memory despite being a generator
fasta_text = file_object.read()
for block in fasta_text.split("\n>")[1:]:
    ...
    yield FastaRecord(header, sequence)

# After — true streaming
for line in file_object:
    if line.startswith(">"):
        if header is not None:
            yield FastaRecord(header, "".join(sequence_lines)...)
        header = line[1:].strip()
        sequence_lines = []
    else:
        sequence_lines.append(line.rstrip("\n"))

• Module docstring: parse_fasta described as "return a list" — corrected to "yield"

db.py

• Missing type annotation: write_fasta's path parameter was untyped — added str
• Loose type annotation: skipped_fasta_entries: dict[str, list] → dict[str, list[str]]
• Incomplete warning: add_fasta warning ended with a dangling colon and never printed the skipped headers — now includes them in the log message

tests/integration/test_integration.py

• CustomWriter.write @classmethod stub used self instead of cls

Original prompt

perform a code review on this small accessory library.

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