result_handle = open("ali.xml") 

from Bio.Blast import NCBIXML
blast_records = NCBIXML.parse(result_handle) 

E_VALUE_THRESH = 0.01

for blast_record in blast_records: 
    for alignment in blast_record.alignments:
        for hsp in alignment.hsps:
            if hsp.expect < E_VALUE_THRESH:
                 print '****Alignment****'
                 print 'sequence:', alignment.title
                 print 'length:', alignment.length
                 print 'e value:', hsp.expect
                 print hsp.query[0:75] + '...'
                 print hsp.match[0:75] + '...'
                 print hsp.sbjct[0:75] + '...' 
                 print hsp.score