====== Some Python features ======

===== Types =====
==== Boolean ====
<code python>
True
False
</code>

===== Header, suite/block, clause =====
<code python>
if foo == bar:         # header             clause 1
    print('same')          # suite/block    clause 1
else:                  # header             clause 2
    print('different')     # suite/block    clause 2
</code>

===== Selection =====
==== if, if/else ====

<code python>
if condition:
    suite
</code>

<code python>
if condition:
    suite
else:
    suite
</code>

=== nested if/else ===

<code python>
if credits == 90:
    print('Senior')
else
    if credits == 60:
        print('Junior')
    else:
        if credits >= 40:
            print('Sophomore')
        else:
            print('something else')
</code>

<code python>
if credits >= 90:
    print('Senior')
elif credits >= 60:
    print('Junior')
elif credits >= 40:
    print('Sophomore')
else:
    print('something else')
</code>

===== Iteration/repetition =====
<code python>
while condition:
    suite:
</code>

**definite loop**: counter controlled repetition, "a program loop in which the number of times the loop will iterate can be determined before the loop is executed."

**indefinite loop**: sentinel controlled repetition, "a program loop in which the number of times the loop will iterate is not known before the loop is executed."

**flag/semaphore/sentinel**: TODO.