I can no longer run python on my mac.  Upgraded to mac OS X 10.11.4 Beta and now if I run python it gets killed.
$python
Killed: 9
the system log shows:
taskgated[396]: killed pid 954 because its code signature is invalid (error -67030)
This seems to be fixed in TODAY's beta release:  15E39d
Why is mac OS X killing python?