[Python] python date interval intersection

As a matter of general interest I'm wondering if there's a more elegant/efficient way to do this. I have a function that compares two start/end tuples of dates returning true if they intersect.

from datetime import date
def date_intersection(t1, t2):
t1start, t1end = t1[0], t1[1]
t2start, t2end = t2[0], t2[1]

if t1end < t2start: return False
if t1end == t2start: return True
if t1start == t2start: return True
if t1start < t2start and t2start < t1end: return True
if t1start > t2start and t1end < t2end: return True
if t1start < t2start and t1end > t2end: return True
if t1start < t2end and t1end > t2end: return True
if t1start > t2start and t1start < t2end: return True
if t1start == t2end: return True
if t1end == t2end: return True
if t1start > t2end: return False


so if:

d1 = date(2000, 1, 10)
d2 = date(2000, 1, 11)
d3 = date(2000, 1, 12)
d4 = date(2000, 1, 13)


then:

>>> date_intersection((d1,d2),(d3,d4))
False
>>> date_intersection((d1,d2),(d2,d3))
True
>>> date_intersection((d1,d3),(d2,d4))
True


etc.

I'm curious to know if there's a more pythonic/elegant/more efficient/less verbose/generally better, way to do this with maybe mxDateTime or some clever hack with timedelta or set()?

An alternative and useful form would be for the function to return a start/end tuple of the intersection if one is found

Thanks

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