if __name__ == "__main__":
    # Aufgabe 6.1
    string_with_spaces = "This is a test"
    string_with_dashes = string_with_spaces.replace(" ", "-")
    print(string_with_dashes)

    # Aufgabe 6.2
    s1 = "Hello, World"
    s2 = s1[s1.find(","):0:-1]
    print(s2)