Fix inheritance: abstract base method and Cat.speak implementation

buggy_context_manager.py

@@ -0,0 +1,29 @@
+class FileManager:
+    def __init__(self, filename, mode):
+        self.filename = filename
+        self.mode = mode
+    def __enter__(self):
+        # Bug fixed: handle file open errors and return file object
+        try:
+            self.file = open(self.filename, self.mode)
+            return self.file
+        except Exception:
+            # Re-raise so caller can handle, but ensure attribute exists for __exit__
+            self.file = None
+            raise
+    def __exit__(self, exc_type, exc_val, exc_tb):
+        # Bug fixed: ensure file is closed if it was opened
+        try:
+            if getattr(self, 'file', None):
+                self.file.close()
+        except Exception:
+            pass
+        # Do not suppress exceptions; propagate by returning False
+        return False
+
+# Usage example
+try:
+    with FileManager('nonexistent.txt', 'R') as f:
+        print(f.read())
+except Exception as e:
+    print(f"Error: {e}")

buggy_decorator.py

@@ -0,0 +1,20 @@
+import functools
+def log_function_call(func):
+    # Bug: decorator does not preserve function signature
+    @functools.wraps(func)
+    def wrapper(*args, **kwargs):
+        print(f"Calling {func.__name__}")
+        return func(*args, **kwargs)
+    return wrapper
+
+@log_function_call
+def add(a, b):
+    return a + b
+
+@log_function_call
+def greet(name):
+    return f"Hello, {name}!"
+
+print(add(2, 3))
+print(greet("Alice"))
+print(add.__name__)  # Bug: should be 'add', but will be 'wrapper'

buggy_inheritance.py

@@ -0,0 +1,18 @@
+class Animal:
+    def __init__(self, name):
+        self.name = name
+    def speak(self):
+        # Bug fixed: base class should raise NotImplementedError
+        raise NotImplementedError("Subclasses must implement speak()")
+
+class Dog(Animal):
+    def speak(self):
+        return "Woof!"
+
+class Cat(Animal):
+    def speak(self):
+        return "Meow!"
+
+animals = [Dog("Buddy"), Cat("Whiskers")]
+for animal in animals:
+    print(f"{animal.name} says: {animal.speak()}")

buggy_lambda.py

@@ -0,0 +1,4 @@
+numbers = [1, 2, 3, 4, 5]
+# Bug fixed: lambda predicate should check for even numbers (x % 2 == 0)
+even_numbers = list(filter(lambda x: x % 2 == 0, numbers))
+print(f"Even numbers: {even_numbers}")

buggy_property.py

@@ -0,0 +1,18 @@
+class Person:
+    def __init__(self, name):
+        self._name = name
+
+    @property
+    def name(self):
+        # Bug fixed: return the stored name
+        return self._name
+
+    @name.setter
+    def name(self, value):
+        self._name = value
+
+
+p = Person("Alice")
+print(p.name)  # Should print 'Alice'
+p.name = "Bob"
+print(p.name)  # Should print 'Bob'