You can use regex here:
>>> import re
>>> strs = "foo\tbar\t\tspam"
>>> re.split(r'\t+', strs)
['foo', 'bar', 'spam']
update:
You can use str.rstrip to get rid of trailing '\t' and then apply regex.
>>> yas = "yas\t\tbs\tcda\t\t"
>>> re.split(r'\t+', yas.rstrip('\t'))
['yas', 'bs', 'cda']