Add compliant and noncompliant examples of python/notebook-variable-redefinition@v1.0

src/python/detectors/notebook_variable_redefinition/notebook_variable_redefinition.py

@@ -0,0 +1,35 @@
+#  Copyright Amazon.com, Inc. or its affiliates. All Rights Reserved.
+#  SPDX-License-Identifier: Apache-2.0
+
+# {fact rule=notebook-variable-redefinition@v1.0 defects=1}
+# —— Code Cell 1 —— #
+import math
+# —— Code Cell 2 —— #
+x = int(input('x:'))
+y = int(input('y:'))
+# —— Code Cell 3 —— #
+z = '5'
+# —— Code Cell 4 —— #
+z = math.sqrt(x**2 + y**2)
+# —— Code Cell 5 —— #
+# Noncompliant: variable `z` is assigned to different types of values in above
+# cells 3 and 4. Then in cell 5, the value of `z` is used in a `print()` call,
+# which can have different result depending on the execution order of cells.
+print('z:', z)
+# {/fact}
+
+
+# {fact rule=notebook-variable-redefinition@v1.0 defects=0}
+# —— Code Cell 1 —— #
+import math
+# —— Code Cell 2 —— #
+x = int(input('x:'))
+y = int(input('y:'))
+# —— Code Cell 3 —— #
+z = '5'
+# —— Code Cell 4 —— #
+# Compliant: Even though there are 2 different types assigned to variable `z`
+# in two different cells, it is only used within one of the two cells.
+z = math.sqrt(x**2 + y**2)
+print('z:', z)
+# {/fact}