Fix iiitv#510: Add Queue [Python] (iiitv#573)

* Add Queue [python]

* Fix Queue title in readme.md

* Small code fix & reordering Queue line in readme.md

* Resolving conflict in readme

README.md

@@ -56,6 +56,7 @@ Community (college) maintained list of Algorithms and Data Structures implementa
 | [AVL Tree](http://www.geeksforgeeks.org/avl-tree-set-1-insertion)|[:white_check_mark:](avl_tree/avl_tree.c)| |[:white_check_mark:](avl_tree/AvlTree.java) | | | | |
 | [Binary Search Tree](https://en.wikipedia.org/wiki/Binary_search_tree) | | | [:white_check_mark:](binary_search_tree/BinarySearchTree.java) | | [:white_check_mark:](binary_search_tree/binary_search_tree.go) | | |
 | [Linked List](https://en.wikipedia.org/wiki/Linked_list) | [:white_check_mark:](linked_list/linkedList.c.c) | | [:white_check_mark:](linked_list/LinkedList.java) | [:white_check_mark:](linked_list/linked_list.py) | [:white_check_mark:](linked_list/linked_list.go) | [:white_check_mark:](linked_list/linkedList.js) | [:white_check_mark:](linked_list/LinkedList.cs) |
+| [Queue](https://en.wikipedia.org/wiki/Queue_(abstract_data_type)) | | | | [:white_check_mark:](queue/queue.py) | | | |
 | [Stack](https://en.wikipedia.org/wiki/Stack_(abstract_data_type)) | [:white_check_mark:](stack/stack.c) | | [:white_check_mark:](stack/Stack.java) | [:white_check_mark:](stack/stack.py) | [:white_check_mark:](stack/stack.go) | [:white_check_mark:](stack/stack.js) | [:white_check_mark:](stack/Stack.cs) |
 | [Trie](https://en.wikipedia.org/wiki/Trie) | | [:white_check_mark:](trie/trie.cpp) | [:white_check_mark:](trie/Trie.java) | | [:white_check_mark:](trie/trie.go) | | [:white_check_mark:](trie/Trie.cs) | |
 | [Queue](https://en.wikipedia.org/wiki/Queue_(abstract_data_type)) | | | [:white_check_mark:](queue/Queue.java) | | | | | |

queue/queue.py

@@ -0,0 +1,48 @@
+class Queue(object):
+
+    def __init__(self):
+        self._list = []
+
+    def count(self):
+        return len(self._list)
+
+    def is_empty(self):
+        return self.count() == 0
+
+    def enqueue(self, item):
+        self._list.append(item)
+
+    def dequeue(self):
+        try:
+            return self._list.pop(0)
+        except IndexError:
+            raise IndexError('pop from empty stack')
+
+
+def main():
+    queue = Queue()
+    n = 100
+
+    print('Empty queue: {0}'.format(queue.is_empty()))
+
+    while queue.count() < 5:
+        print('pushing elements: {0}'.format(n))
+        queue.enqueue(n)
+        n = n + 100
+
+    print('Number of items: {0}'.format(queue.count()))
+    print('Empty queue: {0}'.format(queue.is_empty()))
+
+    while True:
+        try:
+            print('Removing element: {0}'.format(queue.dequeue()))
+        except Exception as e:
+            print('Exception: {0}'.format(e))
+            break
+
+    print('Number of items: {0}'.format(queue.count()))
+    print('Empty queue: {0}'.format(queue.is_empty()))
+
+
+if __name__ == '__main__':
+    main()