Remove any variances that were in CEU population

#use CEU as common variance database, not dbSNP
import sys
def filter_ceu(target_file,background_file='CEU.all.ids'):
    x = []
    for line in file(background_file):
        x.append(line.strip())
    mx = {}.fromkeys(x)
    for line in file(target_file):
        line = line.strip()
        if line.startswith('#'):
            pass
            #print line
        else:
            toks = line.split('\t')
            if not mx.has_key(toks[2]):
                print line
            else:
                pass
    
if __name__=='__main__':
    filter_ceu(sys.argv[1])