PCAP-31-03: Certified Associate Python ProgrammerDemo

The __bases__ attribute belongs to a class and contains a tuple of its direct base classes. It is accessed on the class itself, not on an instance.

The dictionary literal is syntactically invalid because '2' and '3' are not written as key: value entries. Python raises a SyntaxError while parsing the code, before the try/except statement can handle anything.

A three-element list has indices 0 through 2. Assigning a value to index 3 raises IndexError; the except BaseException handler catches it and prints list assignment index out of range.

For a text stream already at end-of-file, readline() returns an empty string. The length of that string is 0, so print(len(d)) prints 0; opening the existing file does not raise IOError.

reversed(string) produces the characters '3', '2', and '1'. Each is converted to an integer and added to dummy, so the printed total is 6.

The conditional my_list[i] % 2 != 0 keeps only values that are not evenly divisible by 2. From the integers 0 through 4, those values are 1 and 3, so the printed list is [1, 3].

Python statements must be separated by a newline or a semicolon. Placing print(m) directly after the closing bracket of the list-comprehension assignment produces a syntax error, so the code does not execute.

Looking up the missing dictionary key '3' raises KeyError. Because KeyError is a built-in exception under BaseException, the handler catches it and print(type(error)) outputs <class 'KeyError'>.

The lambda evaluates 2 % 2 as 0 and 1 % 2 as 1. The function subtracts these values, producing 0 - 1, or -1.

Instance method calls use dynamic dispatch: a.doit() invokes Sub_A.make() and returns 1, while b.doit() invokes Sub_B.make() and returns 2. The printed sum is 3.

Python string membership tests are case-sensitive and determine whether one string occurs as a substring of another. 'not' not in 'in' is true because 'not' does not occur in 'in'. Also, 't'.upper() produces 'T', and 'T' occurs in 'Thames'.

Converting the string '2A' to an integer raises a ValueError. That exception is not handled by the preceding TypeError or LookupError clauses, so the catch-all except clause runs, sets n to 1, and the program prints 1.

When a Python file is run directly, its module name is __main__, so __name__ == '__main__' is true. ClassB directly inherits only from ClassA; therefore, ClassB.__bases__ contains one item and its length is 1.

The loop copies every character from the string representation of 1/3 into dummy. Negative index -1 selects the final character of that string, which is 3, so the code prints 3.

module_a.py is a direct submodule of the pypack package, so it can be imported as pypack.module_a or imported by name from pypack. Python’s package import syntax supports both fully qualified imports and from package import module imports.

A double-leading-underscore method name is name-mangled to _Class__foo within Class. Accessing it externally as o.__foo() does not use the mangled name, so it raises an AttributeError.

A Python class can be instantiated repeatedly to create multiple objects. A subclass commonly represents a more specific form of its superclass, inheriting and potentially extending its attributes and methods.

Dividing by zero raises ZeroDivisionError, a subclass of ArithmeticError. The inner handler increments m and re-raises the exception; the outer ArithmeticError handler catches it and increments m once more. The final value printed is 2.

A Python package groups related Python modules into a common namespace. A standalone Python source file is a module, and .pyc files contain compiled bytecode for modules rather than identifying packages.

dir() returns a list of attribute names rather than a string, making b1 false. An and expression with a false first operand evaluates to False.

ASCII means American Standard Code for Information Interchange. A code point is a numerical value assigned to an encoded character. UTF-8 is not synonymous with ASCII; it is a Unicode encoding that is compatible with ASCII for the first 128 code points. \e denotes an escape character in some contexts, whereas line endings use newline or carriage-return/newline sequences.

split(";") removes the semicolons by separating the text into alphabetic substrings, and ''.join(the_list) concatenates those substrings without separators. The resulting string, "alphabetagamma", consists solely of alphabetic characters, so isalpha() returns True.

Variable is a class attribute and is incremented to 1. Since neither instance overrides Variable, accessing object_2.Variable resolves to that class attribute. object_1.value is its instance attribute and remains 0, so the expression evaluates to 1.

String objects support find, including with an empty string argument. The built-in sorted function accepts strings as iterables and returns a list of sorted characters.