Hi: I am a newbie in this thing of bioinformatics and what I need is to extract a portion of a sequence in FASTA format, for that I have downloaded from ftp.ncbi.nih.gov/genomes/ the fasta file of chromosome 22, which is hsaltHuRef_chr22.fa.gz; and from that file I need to extract from nucleotide 23522552 to nucleotide 23660200 aproximately; how I can do that using BioPython? Also what does these headers refer to inside the fasta file?
gi|157812454|ref|NW001838719.2| Homo sapiens chromosome 22 genomic contig, alternate assembly HuRef DEGEN1103279049253, whole genome shotgun sequence
gi|157697908|ref|NW001838720.1| Homo sapiens chromosome 22 genomic contig, alternate assembly HuRef DEGEN1103279105977, whole genome shotgun sequence
Specially to those numbers, they are making reference to the nucleotide position that I am at that moment?
Thanks for your help