[modeller_usage] gap characters corresponding to the missing residues,

hi i just want to know if there is any script available in modeller that put in dashes (gap character) instead of missing residues when sequence is read from pdb. I am using following script:

from modeller import *# Get the sequence of the 1qg8 PDB file, and write to an alignment filecode = '1qg8'e = environ()m = model(e, file=code)aln = alignment(e)aln.append_model(m, align_codes=code)aln.write(file=code+'.seq')

it is giving me file without missing residues but i need to have dashes in place of missing residues

please reply

thank you