MNT: Dropping Python 3.7 support

Python 3.8 will be the minimum supported version now, along with
Numpy 1.19, which follows NEP29 support intervals. This also bumps
other versions to a 2-year support cycle.

.github/workflows/ci-testing.yml

@@ -11,7 +11,7 @@ jobs:
       fail-fast: false
       matrix:
         os: [ubuntu-latest, macos-latest]
-        python-version: [3.7, 3.8, 3.9]
+        python-version: [3.8, 3.9, '3.10']
     defaults:
       run:
         shell: bash -l {0}
@@ -27,10 +27,10 @@ jobs:
       - name: Minimum packages
         # Only run on Linux for now
         # Conda's linux packages don't grab the testing label of matplotlib causing failures due to freetype differences
-        if: matrix.python-version == '3.7' && matrix.os == 'ubuntu-latest'
+        if: matrix.python-version == '3.8' && matrix.os == 'ubuntu-latest'
         id: minimum-packages
         run: |
-          echo "PACKAGES=cython=0.28.5 matplotlib=3.1 numpy=1.18 owslib=0.17 pyproj=3.0 proj=8.0 scipy=1.2.0 shapely=1.6.4" >> $GITHUB_ENV
+          echo "PACKAGES=cython=0.29.15 matplotlib=3.1 numpy=1.19 owslib=0.19.1 pyproj=3.0 proj=8.0 scipy=1.4.0 shapely=1.6.4" >> $GITHUB_ENV
 
       - name: Latest packages
         if: steps.minimum-packages.conclusion == 'skipped'
@@ -40,7 +40,7 @@ jobs:
       - name: Coverage packages
         id: coverage
         # only want the coverage to be run on the latest ubuntu
-        if: matrix.python-version == '3.9' && matrix.os == 'ubuntu-latest'
+        if: matrix.python-version == '3.10' && matrix.os == 'ubuntu-latest'
         run: |
           echo "PACKAGES=$PACKAGES pytest-cov coveralls" >> $GITHUB_ENV
           echo "CYTHON_COVERAGE=1" >> $GITHUB_ENV

INSTALL

@@ -106,7 +106,7 @@ to the core packages.
 
 Further information about the required dependencies can be found here:
 
-**Python** 3.7 or later (https://www.python.org/)
+**Python** 3.8 or later (https://www.python.org/)
     Python 2 support was removed in v0.19.
 
 **Matplotlib** 3.1 or later (https://matplotlib.org/)

setup.py

@@ -9,11 +9,11 @@
 # and/or pip.
 import sys
 
-PYTHON_MIN_VERSION = (3, 7)
+PYTHON_MIN_VERSION = (3, 8)
 
 if sys.version_info < PYTHON_MIN_VERSION:
     error = """
-Beginning with Cartopy 0.19, Python {} or above is required.
+Beginning with Cartopy 0.21, Python {} or above is required.
 You are using Python {}.
 
 This may be due to an out of date pip.
@@ -57,7 +57,7 @@
 try:
     import numpy as np
 except ImportError:
-    raise ImportError('NumPy 1.10+ is required to install cartopy.')
+    raise ImportError('NumPy 1.19+ is required to install cartopy.')
 
 
 # Please keep in sync with INSTALL file.
@@ -379,9 +379,9 @@ def decythonize(extensions, **_ignore):
             'Programming Language :: C++',
             'Programming Language :: Python',
             'Programming Language :: Python :: 3',
-            'Programming Language :: Python :: 3.7',
             'Programming Language :: Python :: 3.8',
             'Programming Language :: Python :: 3.9',
+            'Programming Language :: Python :: 3.10',
             'Programming Language :: Python :: 3 :: Only',
             'Topic :: Scientific/Engineering',
             'Topic :: Scientific/Engineering :: GIS',