extracting hex mant+exp from double?

[thinkit]

python docs say floats are all doubles...which usually (i think always) is the
IEEE spec for 8-byte float.  are there any routines out there to extract the
binary mantissa and exponent...or better hexadecimal mantissa and exponent out
of the float?  i want to do some statistics but don't want to use decimal.  i
know you can access the 8 bytes with struct lib...then do some bit manipulations
to do the trick.  has anybody done this already?