Add Python bubble sort

[reidhoch]

Fixes Issue #302 (#302)

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Fixes #{ISSUE_NUMBER}

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[sangamcse]

The code does not comply to PEP8.

Origin: PEP8Bear, Section: all.autopep8.

The issue can be fixed by applying the following patch:

--- a/tmp/tmpi7_g_6l6/bubble_sort/Python/bubble_sort.py
+++ b/tmp/tmpi7_g_6l6/bubble_sort/Python/bubble_sort.py
@@ -8,6 +8,7 @@
                 changed = True
     return seq
 
+
 if __name__ == "__main__":
     arr = [64, 34, 25, 12, 22, 11, 90]
     bubble_sort(arr)

[sangamcse]

E305 expected 2 blank lines after class or function definition, found 1

Origin: PycodestyleBear (E305), Section: all.autopep8.