Trying to fix actions.

.github/workflows/test_and_build.yml

@@ -48,8 +48,8 @@ jobs:
                   python-version: ${{ matrix.python-version }}
             - name: Install dependencies
               run: |
-                  python -m pip install --upgrade pip wheel
-                  pip install --upgrade flake8 coverage pytest-cov cython h5py "tables==3.8.0"
+                  python -m pip install --upgrade pip wheel h5py
+                  pip install --upgrade flake8 coverage pytest-cov cython "tables==3.8.0"
                   #pip install git+https://github.com/EconForge/interpolation.py.git
                   pip install -e .
             - name: Lint with flake8

setup.py

@@ -192,10 +192,16 @@ def find_library(library_root, additional_places=None):
 
 def setup_xspec():
 
+    skip_xspec = os.environ.get("SKIP_XSPEC")
     headas_root = os.environ.get("HEADAS")
     conda_prefix = os.environ.get("CONDA_PREFIX")
     xspec_version = os.environ.get("ASTRO_XSPEC_VERSION")
 
+    if skip_xspec is not None:
+
+        print("The SKIP_XSPEC env variable was set. Xspec support will not be installed.")
+        return None
+
     # thanks to the sherpa team for this
 
     if xspec_version is None: