Add code from lecture about iterators

09_python/dict_gen.py

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+a = {k: k * 379 for k in range(10)}
+print(a)

09_python/enum.py

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+els = ["a", "b", "c"]
+
+
+def _enum(els):
+    return zip(range(len(els)), els)
+
+
+for idx, el in _enum(els):
+    print(idx, el)

09_python/for_loop.py

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+class IterableStack:
+    def __init__(self):
+        self._lst = [1, 2, 3, 4, 5]
+
+    def __iter__(self):
+        return ReverseIterator(self._lst)
+
+
+class ReverseIterator:
+    def __init__(self, _lst):
+        self._lst = _lst
+        self.position = len(_lst)
+
+    def __next__(self):
+        self.position -= 1
+        if self.position < 0:
+            raise StopIteration()
+
+        return self._lst[self.position]
+
+
+# container = IterableStack()
+# for v in container:
+#     print(v)
+
+container = IterableStack()
+it_container = iter(container)  # container.__iter__()
+while True:
+    try:
+        v = next(it_container)  # it_container.__next__()
+
+        # тело фора
+        print(v)
+        # конец тела фора
+    except StopIteration:
+        break

09_python/func_stream.py

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+def local_gen():
+    n = 0
+
+    def next():
+        nonlocal n
+        n += 1
+        return n
+
+    return next

09_python/gen.py

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+def _range(start, stop):
+    assert start < stop
+
+    def inside_gen():
+        nonlocal start
+        while start < stop:
+            print("Going to return: ", start)
+            yield start
+            start += 1
+
+        print("here")
+
+    return inside_gen()
+
+
+# for el in _range(0, 10):
+#     print(el)

09_python/lzy_load.py

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+from typing import List
+
+
+def load_files(paths: List[str]):
+    for path in paths:
+        with open(path) as f:
+            yield f.readlines()
+
+
+paths = [
+    "dict_gen.py",
+    "enum.py",
+    "for_loop.py",
+    "gen.py",
+    "lzy_load.py",
+]
+
+for cont in load_files(paths):
+    # code working with content
+    print(cont)