A safer python 3 exec.
Usage:
from execgate import gated_exec, gated_eval, GateSecurityError
foo = gated_eval('1 + 1')
try:
gated_exec("""[
c for c in ().__class__.__bases__[0].__subclasses__() if c.__name__ == "Quitter"
][0](0)()""")
except GateSecurityError:
print("You are a baaaad monkey.")