PCPP-32-101 Sample Questions Answers

Option B is true because the unbind() method is invoked from within a widget’s object 1.

Option D is true because the unbind() method needs the event name as an argument 1.

The unbind() method in Tkinter is used to remove a binding between an event and a function. It can be invoked from within a widget's object when a binding is no longer needed. The method requires the event name as an argument to remove the binding for that specific event. For example:

button = tk.Button(root, text="Click me")

button.bind("", callback_function) # bind left mouse click event to callback_function

button.unbind("") # remove the binding for the left mouse click event

Option A is true because PEP 8 recommends that function and variable names should be lowercase, with words separated by underscores .

Option D is true because PEP 8 recommends that constants should be written in all capital letters with words separated by underscores .

PEP 8 is the official style guide for Python code. It provides guidelines for how to write readable code that follows consistent naming conventions. The aim of PEP 8 is to improve the readability of Python code and make it easier to understand and maintain.

According to PEP 8, variable and function names should be written in all lower-case letters with words separated by underscores, as stated in A. Constants, which are variables whose value is expected to remain constant throughout the code, should be written in all upper-case letters with words separated by underscores, as stated in D.

References:

• PEP 8 -- Style Guide for Python Code: https://www.python.org/dev/peps/pep-0008/
• Python Documentation: https://docs.python.org/3/tutorial/classes.html#classmethods-and-staticmethods

C. The execute method is provided by the Cursor class

This statement is true because the execute method is one of the methods of the Cursor class in the sqlite3 module. The Cursor class represents an object that can execute SQL statements and fetch results from a database connection. The execute method takes an SQL query as an argument and executes it against the database. For example, cur = conn.cursor (); cur.execute (“SELECT * FROM table”) creates and executes a cursor object that selects all rows from a table.

D. The fetchone method returns None when no rows are available

This statement is true because the fetchone method is another method of the Cursor class in the sqlite3 module. The fetchone method fetches the next row of a query result set and returns it as a single tuple or None if no more rows are available. For example, row = cur.fetchone () fetches and returns one row from the cursor object or None if there are no more rows.