new_contents: 
  ###########################################################################
  
  #  Keeps the elements > 200 bp and cleans the headers of fasta sequences
  
  ###########################################################################
  
  from Bio import SeqIO
  from Bio.Seq import Seq
  
  
  infile=open('cryne_library.fasta', 'r')                  # Type here the name of the infile
  outfile=open('cryne_library.fasta_80_200.fasta', 'w')    # Type here the name of the outfile
  
  for record in SeqIO.parse(infile, 'fasta'): 
  	if len(record.seq) > 200:
  		name=str(record.id)
  		name=name.split(';seqs')
  		name2=name[0]
  		name2=name2.replace('centroid=', '')
  		outfile.write('>'+str(name2)+'\n'+str(record.seq)+'\n')
  
  
subject: Create lenght.py