with open(text, 'r') as f:
    list = [line.strip() for line in f]
    list_no = len(list)

import processing
vrtSublist = []
for sllist in range(0,list_no):
    output_vrt = "E:/Sreeraj/Task Global Data CONVERSION/Split/output/task/new1/" + str(sllist) + ".vrt"
    general.runalg("gdalogr:buildvirtualraster",list[sllist],0,True,False,output_vrt)
    vrtSublist.append(str(output_vrt))

y_count = 49
sublists = [vrtSublist[x:x+y_count] for x in xrange(0, len(vrtSublist), y_count)]
if len(vrtSublist) % y_count == 0:
    sublist_no = len(vrtSublist)/y_count
else:
    sublist_no = (len(vrtSublist)/y_count) + 1

Latlist = []
for slsub in range(0,sublist_no):
    output_vrtsublist = "E:/Sreeraj/Task Global Data CONVERSION/Split/output/task/new1/" + "_Lat" + str(slsub) + ".vrt"
    general.runalg("gdalogr:buildvirtualraster",sublists[slsub],0,True,False,output_vrtsublist)
    Latlist.append(str(output_vrtsublist))

Latlist_no = len(Latlist)
output_vrtfinal = "E:/Sreeraj/Task Global Data CONVERSION/Split/output/task/new1/1.vrt"
general.runalg("gdalogr:buildvirtualraster",Latlist,0,True,False,output_vrtfinal)