ODP-2739: Use ambari-python-wrap instead of python

[JeffreySmith]

This moves everything to use ambari-python-wrap instead of python.

[prabhjyotsingh]

@JeffreySmith there are references of #!/usr/bin/env impala-python in some of the files, not sure if that is any important.

Which is hard-coded to

• export IMPALA_PYTHON_VERSION=2.7.16
• export IMPALA_PYTHON3_VERSION=3.7.16

[JeffreySmith]

@prabhjyotsingh
The shebang line can't evaluate environment variables, so impala-python has to be an existing script or binary.

It calls the script IMPALA_HOME/bin/impala-python, which is the following:

source "$(dirname "$0")/impala-python-common.sh"
exec "$PY_ENV_DIR/bin/python" "$@"

impala-python-common.sh then attempts to set up/use a virtual environment, then tries to use that version of python to run whatever script is supposed to run.

I'm not sure why it's set to impala-python since there's also an impala-python3 which does a similar thing. This could be a python 2 & 3 compatibility issue, or it's something being handled somewhere in one of the build scripts.

It doesn't seem to work when used directly; I assume that some build script sets things up correctly, or it could be a build/runtime issue that we find having moved to ambari-python-wrap