If you're a contractor, your best bet is to focus on an industry to understand the needs of that industry better. Rather being a Python developer, you can be a contractor who builds usable solutions that happen to use Python.
Industry knowledge, referrals, good prior work and marketing are important. These $150/hr jobs won't fall into your lap unless you put an effort to position your lap that way :)
As much as we like to think technology is a meritocracy, at the end of the day, it always comes down to who you know. The charitable interpretation of that fact is that there aren't a lot of ways to gauge reputation, so it's mostly about who can vouch for you.
Source: I co-founded a software and design consultancy co-op (https://www.fountstudio.com/about).
In NYC and SF, you'd never fill your contract if you were trying to pay < 150.
For bigger multi month projects i would come down quite a bit, but for small ones i wouldn't budge.
Its not something you can pull off when new to freelancing and more importantly don't have connections / referrals.
Its a comparable price to what small agencies charge (or charged, haven't been working/living in Switzerland in years).
Almost meaningless to talk about hourly rate without also providing the length of the contract.