Update test_tuples.py (trekhleb#6)

* Update test_tuples.py

* Update test_tuples.py

Fixed code style issues. (Trailing whitespace, blank line whitespace and line length too long)

* Update test_tuples.py

* Update test_tuples.py

* Update test_tuples.py

* Update test_tuples.py

* pep8 compliant

Author: TusharShandilya

src/data_types/test_tuples.py

@@ -61,7 +61,7 @@ def test_tuples():
     # pylint: disable=trailing-comma-tuple
     singleton_tuple = 'hello',  # <-- note trailing comma
     assert len(singleton_tuple) == 1
-    assert singleton_tuple == ('hello', )
+    assert singleton_tuple == ('hello',)
 
     # The following example is called tuple packing:
     packed_tuple = 12345, 54321, 'hello!'
@@ -76,3 +76,10 @@ def test_tuples():
     # right-hand side. Sequence unpacking requires that there are as many variables on the left
     # side of the equals sign as there are elements in the sequence. Note that multiple assignment
     # is really just a combination of tuple packing and sequence unpacking.
+
+    # Swapping using tuples.
+    first_number = 123
+    second_number = 456
+    first_number, second_number = second_number, first_number
+    # Data can be swapped from one variable to another in python using
+    # tuples. This eliminates the need to use a 'temp' variable.