import os
import os.path

os.system('cd ......')
for po in range(923,924):


k=po/10
if len(k) == 3:
    fname="........gz"%po
    b=os.path.isfile(fname)
    if b == True:
        os.system('............... '@RGtID:group%dtSM:sample%dtPL:.....tLB:lib1tPU:unit%d' /home/................/........../  /........................000%d_1.gz   /home/............../.....%d_2.gz > /......./myprograms/......s/..........000%d.gz'%(po,po,po,po,po,po))