#!/usr/bin/env python
from Bio import AlignIO,SeqIO
from Bio.PDB import *
import sys, os, re

__date__="10/23/2014"

def loadPDBFile(*file_name):
    for i in file_name:
        print i
        st=PDBParser(QUIET=True).get_structure('X',i)
        ko=st.get_chains()
        for i in ko:
            print i.id # use of the Select class (also in PDBIO). Select has four methods: 
        
        for pp in PPBuilder().build_peptides(st):
            print pp.get_sequence(), len(pp.get_sequence())

#
def checkExtension(*file_name):
    for i in file_name: 
        if not i.endswith(".pdb"):
            print i+" doesn't end with .pdb"
            sys.exit(1)
#
if __name__=="__main__":
    checkExtension(sys.argv[1])
    loadPDBFile(sys.argv[1])