Add private APIs to get Python version before bootstrapping Python. ### Description

Add private APIs (module.\_py_version_{major,minor,micro}) to get the Python version before bootstrapping Python, and use it in Module.preRun to initialize filesystem.

### Checklists

- [x] Add / update tests

package:
  name: galpy
  version: 1.8.1
  top-level:
    - galpy
source:
  url: https://files.pythonhosted.org/packages/97/5b/ef489c571595f753fd86634e93f941897bf3511317ec829f5b080a390bb1/galpy-1.8.1.tar.gz
  sha256: 9e2b55e50aab4aa7f4313ab9c333ac4512a4338e8d111fce5f6c14456ea53a07
build:
  script:
    export LIBGSL_INCLUDE_PATH=$(pkg-config --cflags-only-I --dont-define-prefix gsl)
    export LIBGSL_LIBRARY_PATH=$(pkg-config --libs-only-L --dont-define-prefix gsl)
  cflags: |
    $(LIBGSL_INCLUDE_PATH)
  ldflags: |
    $(LIBGSL_LIBRARY_PATH)
  exports: requested
requirements:
  run:
    - numpy
    - scipy
    - matplotlib
    - astropy
    - future
    - setuptools
  host:
    - libgsl
    - numpy
    - scipy
test:
  imports:
    - galpy
    - galpy.potential
    - galpy.orbit
    - galpy.actionAngle
    - galpy.df
about:
  home: http://github.com/jobovy/galpy
  PyPI: https://pypi.org/project/galpy
  summary: Galactic Dynamics in python
  license: New BSD

package:
  name: galpy
  version: 1.8.1
  top-level:
    - galpy
source:
  url: https://files.pythonhosted.org/packages/97/5b/ef489c571595f753fd86634e93f941897bf3511317ec829f5b080a390bb1/galpy-1.8.1.tar.gz
  sha256: 9e2b55e50aab4aa7f4313ab9c333ac4512a4338e8d111fce5f6c14456ea53a07
build:
  script:
    export LIBGSL_INCLUDE_PATH=$(pkg-config --cflags-only-I --dont-define-prefix gsl)
    export LIBGSL_LIBRARY_PATH=$(pkg-config --libs-only-L --dont-define-prefix gsl)
  cflags: |
    $(LIBGSL_INCLUDE_PATH)
  ldflags: |
    $(LIBGSL_LIBRARY_PATH)
  exports: requested
requirements:
  run:
    - numpy
    - scipy
    - matplotlib
    - astropy
    - future
    - setuptools
  host:
    - libgsl
    - numpy
    - scipy
test:
  imports:
    - galpy
    - galpy.potential
    - galpy.orbit
    - galpy.actionAngle
    - galpy.df
about:
  home: http://github.com/jobovy/galpy
  PyPI: https://pypi.org/project/galpy
  summary: Galactic Dynamics in python
  license: New BSD
