Add Python all

python-all.md

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+# Python all(iterable)
+
+`all()` is a built in function in Python 3, to check if all items of an [_iterable_](https://docs.python.org/3/glossary.html#term-iterable) is `True`. It takes one argument,  `iterable`. 
+
+## Argument
+### iterable
+
+The `iterable` argument is the collection whose all entries are to be checked. It can typically be a `list`, `str`, `dict`, `tuple` etc. 
+
+## Return Value
+The return value would be a boolean. If and only if **all** entries of iterable are `True`, it returns `True`. This function essentially performs a Boolean `AND` operation over all elements.
+
+If even one of them is not `True`, it would return `False`.
+
+The `all()` operation is equivalent to (not internally implemented exactly like this)
+
+```python
+def all(iterable):
+    for element in iterable:
+        if not element:
+            return False
+    return True
+```
+
+## Code Sample
+
+```python
+print(all([6, 7])) #=> True
+print(all([6, 7, None])) #=> False  Because this has None
+print(all([0, 6, 7])) #=> False Because this has zero
+print(all([9, 8, [1, 2]])) #=> True
+print(all([9, 8, []])) #=> False Because it has []
+print(all([9, 8, [1, 2, []]])) #=> True
+print(all([9, 8, {}])) #=> False Because it has {}
+print(all([9, 8, {'engine': 'Gcloud'}])) #=> True
+
+```
+:rocket: [REPL It!](https://repl.it/CL9U/0)
+
+[Documentation](https://docs.python.org/3/library/functions.html#all)