使用fasta文件中的序列ID提取序列

def extract_sequence_from_fasta(fasta_file, sequence_id):
    sequence = ""
    with open(fasta_file, "r") as file:
        lines = file.readlines()
        for line in lines:
            line = line.strip()
            if line.startswith(">"):
                current_sequence_id = line[1:]
                if current_sequence_id == sequence_id:
                    break
            else:
                sequence += line
    return sequence

fasta_file = "example.fasta"
sequence_id = "sequence1"
extracted_sequence = extract_sequence_from_fasta(fasta_file, sequence_id)
print(extracted_sequence)