Strings

Strings are sequence of one or more characters in Python. Strings can be assinged to variables.

In python, strings

1) Immutable 2) Are objects that have methods associated with it.

Let us look at Python string properties through a problem statement.

Problem Statement

Test if a given string is a palindrome.

Write test - 1

def test_palindrome():
    assert is_a_palindrome("ABBA") == True
    assert is_a_palindrome("BOB")  == True
    assert is_a_palindrome("B") == Tru

Exercise Test - 1

    def test_palindrome():
>       assert is_a_palindrome("ABBA") == True
E       NameError: name 'is_a_palindrome' is not defined

Fix Test - 1

def is_a_palindrome(term) -> bool:
    return False


def test_palindrome():
    assert is_a_palindrome("ABBA") == True
    assert is_a_palindrome("BOB")  == True
    assert is_a_palindrome("B") == True

Exercise Test - 2

    def test_palindrome():
>       assert is_a_palindrome("ABBA") == True
E       AssertionError: assert False == True
E        +  where False = is_a_palindrome('ABBA')

strings/palindrome_2.py:6: AssertionError

Fix Test - 2

def is_a_palindrome(term) -> bool:
    reversed_term = term[::-1]
    if reversed_term == term:
        return True
    return False


def test_palindrome():
    assert is_a_palindrome("ABBA") == True
    assert is_a_palindrome("BOB")  == True
    assert is_a_palindrome("B") == True
    assert is_a_palindrome("NOT") == False

Exercise Tests - 2

strings/palindrome_3.py .                                                                                                                                                                                                                                         [100%]

1 passed in 0.01s

Refactor

def is_a_palindrome(term) -> bool:
    return term == term[::-1]


def test_palindrome():
    assert is_a_palindrome("ABBA") == True
    assert is_a_palindrome("BOB") == True
    assert is_a_palindrome("B") == True
    assert is_a_palindrome("NOT") == False