Add Task headers

Author: kochaika

Strings/Basic string methods/task.md

@@ -9,6 +9,7 @@ Detailed information about all string methods can be found <a href="https://docs
 
 For more structured and detailed information, you can refer to [this Hyperskill knowledge base page](https://hyperskill.org/learn/step/6842).
 
+### Task
 Print `monty_python` in upper case using an appropriate string method.  
 
 <div class='hint'>Pay attention to how the <code>lower()</code> method is used in our code.</div>

Strings/Character escaping/task-info.yaml

@@ -3,7 +3,7 @@ files:
   - name: character_escaping.py
     visible: true
     placeholders:
-      - offset: 157
+      - offset: 205
         length: 47
         placeholder_text: ???
   - name: tests/__init__.py

Strings/Character escaping/task.md

@@ -20,6 +20,7 @@ You can learn more about escaping from <a href="https://docs.python.org/3/refere
 
 For more structured and detailed information, you can also refer to [this Hyperskill knowledge base page](https://hyperskill.org/learn/step/7130).
 
+### Task
 Print out the following text using one string:  
 ```text
 The name of this ice cream is "Sweet'n'Tasty"  

Strings/F-strings/task.md

@@ -31,6 +31,7 @@ For more information about formatted string literals you can refer to <a href="h
 
 For more structured and detailed information, you can also refer to [this Hyperskill knowledge base page](https://hyperskill.org/learn/step/6037).
 
+### Task
 Try creating an f-string yourself. Also try running the code to see what it prints.
 
 <div class="hint">The value assigned to the <code>name</code> variable has to be a string, so it needs to be in quotes, 

Strings/In operator/task.md

@@ -3,6 +3,7 @@
 If you want to check whether a string contains a specific letter or a substring, 
 you can use the `in` keyword.  
 
+### Task
 Check if there is `"ice"` in `"ice cream"` and assign the result to the variable `contains`.  
 
 <div class="hint">Use the <code>in</code> operator.</div>

Strings/String formatting/task.md

@@ -15,6 +15,7 @@ or decimal values.
 
 For more structured and detailed information, you can refer to [this Hyperskill knowledge base page](https://hyperskill.org/learn/step/6037).
 
+### Task
 Tell PyCharm how old you are (using digits).  
 
 <div class='hint'>Use the <code>%d</code> special symbol.</div>

Strings/String indexing/task.md

@@ -11,6 +11,7 @@ Note that since `-0` is the same as `0` , negative indices start from `-1`.
 
 For more structured and detailed information, you can refer to [this Hyperskill knowledge base page](https://hyperskill.org/learn/step/6189).
 
+### Task
 Use the index operator to get the letter `"P"` from `"Python"` .  
 
 <div class="hint">Note that indices start with 0.</div>

Strings/String length/task.md

@@ -17,6 +17,7 @@ print(type(a))  # <class 'float'>
 
 For more structured and detailed information, you can refer to [this Hyperskill knowledge base page](https://hyperskill.org/learn/step/5814).
 
+### Task
 Get the first half of the string stored in the variable `phrase`.  
 Note: when getting the index, remember about type conversion.  
 

Strings/String negative indexing/task.md

@@ -5,6 +5,7 @@ from the end of a string.
 
 For more structured and detailed information, you can refer to [this Hyperskill knowledge base page](https://hyperskill.org/learn/step/6189).
 
+### Task
 Use a negative index to get the `'!'` sign from `long_string`.   
 
 <div class='hint'>Use a negative index.</div>

Strings/String slicing/task.md

@@ -26,6 +26,7 @@ str[:]         # a copy of the whole array
 
 For more structured and detailed information, you can refer to [this Hyperskill knowledge base page](https://hyperskill.org/learn/step/6177).
 
+### Task
 Use slicing to get `"Python"` from the `monty_python` variable.  
 
 <div class='hint'>You can leave one of the indices empty.</div>