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@section('title')
    Lab 2: Extra motifs
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# Lab 2: Extra motifs

These extra exercises build on the [motifs functions](motifs); if you
haven't finished that part you should do that first.

## Create a user-specified motif

<div class="partnerA">Partner A</div>

Write a function called `customNotes` which takes zero parameters. It
will use `input` to ask the user for a total duration as well as two
integers specifying how far up to climb between the 1st and 2nd, and 2nd
and 3rd notes of a motif. It will then add **three** motifs using those
two parameters, such that the total duration of all three matches the
requested duration* motifs using those two parameters, such that the
total duration of all three matches the requested duration.

<p id="customDesc" markdown="1">
Depending on what you type it, this will sound different every time.
Here is an example of what this would sound like if the user enters 3 for
the duration, -2 for the first gap, and 4 for the second gap:
</p>

<audio controls aria-describedby="customDesc">
  <source src="/content/labs/lab02/custom.wav" type="audio/wav">
  Your browser does not support the audio element.
  <a href="/content/labs/lab02/custom.wav">
    Click here to download `custom.wav`
  </a>
  which you can open with a media player program on your computer.
</audio>

The printed output (including the prompts and inputs provided) should
look like this:

<pre>
<code class="language-txt">
What should the duration be? <span class="input">3</span>
How far between notes 1 and 2? <span class="input">-2</span>
How far between notes 2 and 3? <span class="input">4</span>
a 0.333s keyboard note at C4 (60% vol)
and a 0.333s keyboard note at A3 (60% vol)
and a 0.333s keyboard note at E4 (60% vol)
and a 0.333s keyboard note at E4 (60% vol)
and a 0.333s keyboard note at C4 (60% vol)
and a 0.333s keyboard note at G4 (60% vol)
and a 0.333s keyboard note at G4 (60% vol)
and a 0.333s keyboard note at E4 (60% vol)
and a 0.333s keyboard note at B4 (60% vol)
</code>
</pre>

Hints:

1. You'll have to enable the test for `customNotes` in `test_motifs.py`,
    and you should disable the other tests for clarity.
2. You will need to convert the duration to a number, and then calculate
    the per-motif duration from that. You should probably convert it to a
    floating-point number in case someone types in a fractional number of
    seconds.
3. When you run `test_motifs.py`, nothing will happen until you finish
    entering the inputs it requests.
4. You should call `motif` rather than copying and pasting code to create
    the notes.


## Challenge: Add some random beats to your motifs

<div class="partnerB">Partner B</div>

<p id="randomDesc" markdown="1">
Write a function called `randomBeatsNotes` which adds the same notes as
`climbingNotes` does (it should in fact call `climbingNotes` to achieve
that) but which also adds three beats at random points while the notes
are playing, one during each copy of the motif.
</p>

Here is what the result might sound like, although it will sound
different every time.

<audio controls aria-describedby="randomDesc">
  <source src="/content/labs/lab02/random.wav" type="audio/wav">
  Your browser does not support the audio element.
  <a href="/content/labs/lab02/random.wav">
    Click here to download `random.wav`
  </a>
  which you can open with a media player program on your computer.
</audio>

How can we pick something randomly? Python has a built-in `random` module
for that. You'll need to import it, just like you've been importing other
modules like `turtle`. One of the functions it provides is called
[`random`](/reference/quickref#random) which picks a random number
between 0 and 1, that we can multiply by a number of seconds to pick a
delay value up to a specific maximum delay. [Our quick-reference
page](/reference/quickref#seed) has documentation on a few other
functions in the `random` module as well.


Hints: 
1. `randomBeatsNotes` will have 1 parameter: the total duration (just
    like `climbingNotes` does).
2. The duration of each beat is 1/2 the duration of the notes (so 1/6 the
    duration of each motif). Their volume has been set 4 steps
    [`quieter`](/reference/quickref#quieter) than the base volume.
2. Writing a separate function to place one random beat within a specific
    time interval is a good approach
4. Ideally, the beats should end before the end of their assocaited
    motifs, but its okay if yours have a chance of lasting beyond the end
    of their motif.

You use the prepared line of code in `test_motifs.py` to test your
function.

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