finish test harness and add basic tests

local_tests/python_function_tests.py

@@ -0,0 +1,40 @@
+import os
+from test_models import PythonFunctionTest
+
+tests = []
+
+def register_test(function, name=None, output_file=None, desc=None):
+    if not os.path.exists(output_file):
+        raise FileNotFoundError(f'Error creating test {name}: cannot find file {output_file}.')
+    output = open(output_file).read()
+    tests.append(PythonFunctionTest(
+            function, name=name, output=output, desc=desc
+        ))
+
+
+#######################################
+##            BEGIN TESTS            ##
+#######################################
+
+#
+#
+#
+def check_gpu_count():
+    import torch
+    num_gpus = torch.cuda.device_count()
+    if num_gpus == 0:
+        print(f'Error: detected 0 GPUs. Must run local tests with multiple GPUs. Perhaps you need to configure CUDA?')
+    
+register_test(check_gpu_count, name='check CUDA', 
+    output_file='local_tests/outputs/empty_file.txt', 
+    desc='Makes sure CUDA is enabled, properly configured, and detects at least 1 GPU')
+
+#
+# test: import textattack
+#
+def import_textattack():
+    import textattack
+    
+register_test(import_textattack, name='import textattack', 
+    output_file='local_tests/outputs/empty_file.txt', 
+    desc='Makes sure the textattack module can be imported')