Update use of setuptools_scm

Author: saimn

.gitignore

@@ -15,3 +15,4 @@ api/
 build/
 docs/_build
 htmlcov/
+muse_psfr/version.py

muse_psfr/__init__.py

@@ -13,12 +13,5 @@ def _setup_logging():
 
 _setup_logging()
 
-from pkg_resources import DistributionNotFound, get_distribution  # noqa
-
 from .psfrec import *  # noqa
-
-try:
-    __version__ = get_distribution(__name__).version
-except DistributionNotFound:  # pragma: no cover
-    # package is not installed
-    pass
+from .version import version as __version__  # noqa

pyproject.toml

@@ -0,0 +1,5 @@
+[build-system]
+requires = ["setuptools>=45", "setuptools_scm[toml]>=6.2", "wheel"]
+
+[tool.setuptools_scm]
+write_to = "muse_psfr/version.py"

setup.cfg

@@ -13,9 +13,10 @@ classifiers =
     License :: OSI Approved :: MIT License
     Operating System :: OS Independent
     Programming Language :: Python :: 3
-    Programming Language :: Python :: 3.6
     Programming Language :: Python :: 3.7
     Programming Language :: Python :: 3.8
+    Programming Language :: Python :: 3.9
+    Programming Language :: Python :: 3.10
     Programming Language :: Python :: Implementation :: CPython
     Topic :: Scientific/Engineering :: Astronomy
     Topic :: Scientific/Engineering :: Physics
@@ -24,9 +25,7 @@ classifiers =
 zip_safe = False
 include_package_data = True
 packages = find:
-python_requires = >=3.6
-setup_requires =
-    setuptools_scm
+python_requires = >=3.7
 install_requires =
     mpdaf
     astropy