Is Python's time.time() timezone specific?

Yes, time.time() returns the number of seconds since an unspecified epoch. Note that on most systems, this does not include leap seconds, although it is possible to configure your system clock to include them. On cpython, time.time is implemented as a call to the C function time, which per §27.23.2.4.2 of the C standard does not have to use a specified epoch:

The time function determines the current calendar time. The encoding of the value is unspecified.

On virtually every OS (including Linux, Mac OSX, Windows, and all other Unixes), the epoch is 1970-1-1, 00:00 UTC, and on these systems time.time is timezone-independent.

The return value should be the same, since it's the offset in seconds to the UNIX Epoch.

That being said, if you convert it to a Date using different timezones, the values will, of course, differ.

If, from those Dates, you convert each of them to UTC, then the result has to be the same.

time.time() returns the number of seconds since the UNIX epoch began at 0:00 UTC, Jan 1, 1970. Assuming the machines have their clocks set correctly, it returns the same value on every machine.