<s>[INST] Terminating a Python script I am aware of the die() command in PHP which stops a script early.
How can I do this in Python?
 [/INST] import sys
sys.exit()

details from the sys module documentation:

sys.exit([arg])

Exit from Python. This is implemented by raising the
    SystemExit exception, so cleanup actions specified by finally clauses
    of try statements are honored, and it is possible to intercept the
    exit attempt at an outer level.
The optional argument arg can be an integer giving the exit status
    (defaulting to zero), or another type of object. If it is an integer,
    zero is considered âsuccessful terminationâ and any nonzero value is
    considered âabnormal terminationâ by shells and the like. Most systems
    require it to be in the range 0-127, and produce undefined results
    otherwise. Some systems have a convention for assigning specific
    meanings to specific exit codes, but these are generally
    underdeveloped; Unix programs generally use 2 for command line syntax
    errors and 1 for all other kind of errors. If another type of object
    is passed, None is equivalent to passing zero, and any other object is
    printed to stderr and results in an exit code of 1. In particular,
    sys.exit("some error message") is a quick way to exit a program when
    an error occurs.
Since exit() ultimately âonlyâ raises an exception, it will only exit
    the process when called from the main thread, and the exception is not
    intercepted.


Note that this is the 'nice' way to exit.  @glyphtwistedmatrix below points out that if you want a 'hard exit', you can use os._exit(errorcode), though it's likely os-specific to some extent (it might not take an errorcode under windows, for example), and it definitely is less friendly since it doesn't let the interpreter do any cleanup before the process dies.
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