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# Raindrops

Your task is to convert a number into a string that contains raindrop sounds corresponding to certain potential factors. A factor is a number that evenly divides into another number, leaving no remainder. The simplest way to test if a one number is a factor of another is to use the [modulo operation](https://en.wikipedia.org/wiki/Modulo_operation).

The rules of `raindrops` are that if a given number:

- has 3 as a factor, add 'Pling' to the result.
- has 5 as a factor, add 'Plang' to the result.
- has 7 as a factor, add 'Plong' to the result.
- _does not_ have any of 3, 5, or 7 as a factor, the result should be the digits of the number.

## Examples

- 28 has 7 as a factor, but not 3 or 5, so the result would be "Plong".
- 30 has both 3 and 5 as factors, but not 7, so the result would be "PlingPlang".
- 34 is not factored by 3, 5, or 7, so the result would be "34".


## Exception messages

Sometimes it is necessary to raise an exception. When you do this, you should include a meaningful error message to
indicate what the source of the error is. This makes your code more readable and helps significantly with debugging. Not
every exercise will require you to raise an exception, but for those that do, the tests will only pass if you include
a message.

To raise a message with an exception, just write it as an argument to the exception type. For example, instead of
`raise Exception`, you should write:

```python
raise Exception("Meaningful message indicating the source of the error")
```

## Running the tests

To run the tests, run `pytest raindrops_test.py`

Alternatively, you can tell Python to run the pytest module:
`python -m pytest raindrops_test.py`

### Common `pytest` options

- `-v` : enable verbose output
- `-x` : stop running tests on first failure
- `--ff` : run failures from previous test before running other test cases

For other options, see `python -m pytest -h`

## Submitting Exercises

Note that, when trying to submit an exercise, make sure the solution is in the `$EXERCISM_WORKSPACE/python/raindrops` directory.

You can find your Exercism workspace by running `exercism debug` and looking for the line that starts with `Workspace`.

For more detailed information about running tests, code style and linting,
please see [Running the Tests](http://exercism.io/tracks/python/tests).

## Source

A variation on FizzBuzz, a famous technical interview question that is intended to weed out potential candidates. That question is itself derived from Fizz Buzz, a popular children's game for teaching division. [https://en.wikipedia.org/wiki/Fizz_buzz](https://en.wikipedia.org/wiki/Fizz_buzz)

## Submitting Incomplete Solutions

It's possible to submit an incomplete solution so you can see how others have completed the exercise.