Created Open file

Author: sofiiako

File input output/Open file/input.txt

@@ -0,0 +1,4 @@
+This is the first line of the file.
+Second line of the file.
+Here's another one!
+The last line.

File input output/Open file/input1.txt

@@ -0,0 +1 @@
+This is the entire file.

File input output/Open file/task-info.yaml

@@ -0,0 +1,17 @@
+type: edu
+files:
+- name: task.py
+  visible: true
+  placeholders:
+  - offset: 152
+    length: 37
+    placeholder_text: '# Open the file input1.txt in read mode using the with statement'
+  - offset: 396
+    length: 15
+    placeholder_text: '# Close the output file!'
+- name: tests.py
+  visible: false
+- name: input.txt
+  visible: true
+- name: input1.txt
+  visible: true

File input output/Open file/task.md

@@ -0,0 +1,37 @@
+## Open file
+Python has a number of built-in functions to read and write information to a file on your computer.
+
+`open()` returns a file object, and is most commonly used with two arguments: `open(filename, mode)`:
+```python
+f = open('somefile.txt', 'w')
+```
+The first argument is a string containing the filename. The second argument is another string containing
+a few characters describing the way in which the file will be used. mode can be `"r"` when the file
+will only be read, `"w"` for only writing (an existing file with the same name will be erased), and
+'a' opens the file for appending; any data written to the file is automatically added to the end.
+`"r+"` opens the file for both reading and writing. The mode argument is optional; `"r"` will be assumed
+if it’s omitted.
+
+It is good practice using the `with` keyword when dealing with file objects. The advantage is that the
+file is properly closed after its suite finishes.
+
+```python
+with open('somefile.txt') as f:
+    read_data = f.read()
+
+# We can check that the file has been automatically closed.
+f.closed
+```
+```text
+True
+```
+**Important**: If you’re not using the `with` keyword, then you should call `f.close()` to close the file and
+immediately free up any system resources used by it. After a file object is closed, either by a `with` statement or by calling `f.close()`, attempts to use the file object
+will automatically fail.
+
+In the code editor, open the file `input1.txt` in read mode properly using the `with` statement. Check out the
+name that is used for the file in the later code and use it. Afterwards, close the output file using the 
+`close()` method.
+
+<div class="hint">Supply the <code>r</code> argument to the method <code>open()</code>,
+just for the sake of practicing!</div>

File input output/Open file/task.py

@@ -0,0 +1,12 @@
+with open('input.txt', 'r') as my_file:
+    # Some action performed with the file, the read() method explained later.
+    print(my_file.read(), '\n')
+
+
+with open('input1.txt', 'r') as file:
+    print(file.read())
+
+
+outfile = open('outfile.txt', 'w') # opening the file in write mode (using `w` argument)
+outfile.write('Hello World')  # writing to the file, the write() method is explained later.
+outfile.close()

File input output/Open file/tests.py

@@ -0,0 +1,41 @@
+from test_helper import run_common_tests, failed, passed, get_answer_placeholders, get_file_output
+
+
+def test_window():
+    window = get_answer_placeholders()[0]
+    if "with open(" in window:
+        passed()
+    else:
+        failed("Use with open syntax.")
+
+
+def test_window1():
+    window = get_answer_placeholders()[0]
+    if "as file:" in window:
+        passed()
+    else:
+        failed("The file should be named 'file'.")
+
+
+def test_window2():
+    window = get_answer_placeholders()[0]
+    if "'r'" in window or '"r"' in window:
+        passed()
+    else:
+        failed("Add the 'r' argument!")
+
+
+def test_window3():
+    window = get_answer_placeholders()[1]
+    if 'outfile.close()' in window:
+        passed()
+    else:
+        failed("Close the outfile properly, use the f.close() syntax.")
+
+
+if __name__ == '__main__':
+    run_common_tests()
+    test_window()
+    test_window1()
+    test_window2()
+    test_window3()

File input output/lesson-info.yaml

@@ -1,4 +1,6 @@
 custom_name: File input/output
 content:
+- Open file
 - Read file
 - Write to file
+