MAINT: Remove Numba < 0.49.0 support

Author: oyamad

Diff for: docs/rtd-requirements.txt

@@ -1,7 +1,7 @@
 sphinx
 ipython
 numpydoc
-numba>=0.38
+numba>=0.49
 numpy>=1.17
 sympy
 scipy>=1.5

Diff for: pyproject.toml

@@ -21,7 +21,7 @@ keywords = [
 dynamic = ["description", "version"]
 requires-python = ">=3.7"
 dependencies = [
-    'numba',
+    'numba>=0.49.0',
     'numpy>=1.17.0',
     'requests',
     'scipy>=1.5.0',

Diff for: quantecon/util/numba.py

@@ -5,10 +5,7 @@
 import numpy as np
 from numba import jit, types
 from numba.extending import overload
-try:
-    from numba.np.linalg import _LAPACK  # for Numba >= 0.49.0
-except ModuleNotFoundError:
-    from numba.targets.linalg import _LAPACK  # for Numba < 0.49.0
+from numba.np.linalg import _LAPACK
 
 
 # BLAS kinds as letters