diff --git a/implement-shell-tools/cat/notes.js b/implement-shell-tools/cat/notes.js
new file mode 100644
index 00000000..dc54e635
--- /dev/null
+++ b/implement-shell-tools/cat/notes.js
@@ -0,0 +1,38 @@
+import process from "node:process";
+import { promises as fs } from "node:fs";
+// const fs = promises
+
+// * `cat sample-files/1.txt`
+// * `cat -n sample-files/1.txt`
+// * `cat sample-files/*.txt`
+// * `cat -n sample-files/*.txt`
+// * `cat -b sample-files/3.txt`
+
+//from coursework
+// const content = await fs.readFile(path, "utf-8");
+// const countOfWordsContainingEs = content
+//   .split(" ")
+//   .filter((word) => word.includes("e"))
+//   .length;
+// console.log(countOfWordsContainingEs);
+
+// process.argv documentation that process.argv[0] will be the path to node
+// process.argv[1] will be the path to this file
+// the arguments start at index 2
+
+
+
+// 1 `cat sample-files/1.txt`
+// async function caseOne(oneFile) {
+//     const content = await fs.readFile(file, "utf-8");
+//     console.log(content);
+// }
+// 3 `cat sample-files/*.txt`
+// async function caseThree(listOfFiles) {
+//     for (const file of listOfFiles) {
+//         const content = await fs.readFile(file, "utf-8");
+
+//         console.log(content);
+//   }
+// }
+
diff --git a/implement-shell-tools/ls/index.js b/implement-shell-tools/ls/index.js
new file mode 100644
index 00000000..c8d962a8
--- /dev/null
+++ b/implement-shell-tools/ls/index.js
@@ -0,0 +1,50 @@
+// fs.readdir
+import process from "node:process";
+import { promises as fs } from "node:fs";
+
+
+//  `ls -1`
+async function showAllFilesInDir(directory) {
+    const listOfFiles = await fs.readdir(directory); 
+    
+    for (const eachFile of listOfFiles) { 
+        console.log(eachFile);
+    }
+}
+
+// `ls -1 sample-files`
+async function showVisibleInSampleFiles() {
+        const listOfFiles = await fs.readdir('sample-files'); 
+    
+    for (const eachFile of listOfFiles) { 
+        if (eachFile[0] !== '.') {
+             console.log(eachFile);
+        }
+       
+    }
+}
+
+
+// `ls -1 -a sample-files`
+async function showAllInSampleFiles() {
+        const listOfFiles = await fs.readdir('sample-files'); 
+    
+    for (const eachFile of listOfFiles) { 
+        
+        console.log(eachFile);
+    
+    }
+}
+
+
+
+const argv = process.argv.slice(2);
+
+if (argv.includes('-a')) {
+    await showAllInSampleFiles();
+} else if (argv.includes('sample-files')) {
+    await showVisibleInSampleFiles();
+} else {
+    await showCurrentDir();
+}
+
diff --git a/individual-shell-tools/ls/script-02.sh b/individual-shell-tools/ls/script-02.sh
index d0a5a10f..9fa05d88 100755
--- a/individual-shell-tools/ls/script-02.sh
+++ b/individual-shell-tools/ls/script-02.sh
@@ -4,3 +4,4 @@ set -euo pipefail
 
 # TODO: Write a command which lists all of the files in the directory named child-directory.
 # The output should be a list of names: helper-1.txt, helper-2.txt, helper-3.txt.
+ls child-directory
\ No newline at end of file
diff --git a/prep/1.py b/prep/1.py
new file mode 100644
index 00000000..0c87a0ef
--- /dev/null
+++ b/prep/1.py
@@ -0,0 +1,10 @@
+# ✍️exercise
+# Predict what double("22") will do. Then run the code and check. Did it do what you expected? 
+# Why did it return the value it did?
+
+def double(value):
+    return value * 2 
+
+#2222
+
+print(double("22"))
\ No newline at end of file
diff --git a/prep/10.py b/prep/10.py
new file mode 100644
index 00000000..b7a435bd
--- /dev/null
+++ b/prep/10.py
@@ -0,0 +1,60 @@
+# ✍️exercise
+# Try changing the type annotation of Person.preferred_operating_system 
+# from str to List[str].
+
+# Run mypy on the code.
+
+# It tells us different places that our code is now wrong, because we’re 
+# passing values of the wrong 
+# type.
+
+# We probably also want to rename our field - lists are plural. Rename 
+# the field to preferred_operating_systems.
+
+# Run mypy again.
+
+# Fix all of the places that mypy tells you need changing. Make sure the 
+# program works as you’d expect.
+
+from dataclasses import dataclass
+from typing import List
+
+@dataclass(frozen=True)
+class Person:
+    name: str
+    age: int
+    preferred_operating_systems: List[str]
+
+
+@dataclass(frozen=True)
+class Laptop:
+    id: int
+    manufacturer: str
+    model: str
+    screen_size_in_inches: float
+    operating_system: str
+
+
+def find_possible_laptops(laptops: List[Laptop], person: Person) -> List[Laptop]:
+    possible_laptops = []
+    for laptop in laptops:
+        if laptop.operating_system == person.preferred_operating_systems:
+            possible_laptops.append(laptop)
+    return possible_laptops
+
+
+people = [
+    Person(name="Imran", age=22, preferred_operating_systems=["Ubuntu"]),
+    Person(name="Eliza", age=34, preferred_operating_systems=["Arch Linux"]),
+]
+
+laptops = [
+    Laptop(id=1, manufacturer="Dell", model="XPS", screen_size_in_inches=13, operating_system="Arch Linux"),
+    Laptop(id=2, manufacturer="Dell", model="XPS", screen_size_in_inches=15, operating_system="Ubuntu"),
+    Laptop(id=3, manufacturer="Dell", model="XPS", screen_size_in_inches=15, operating_system="ubuntu"),
+    Laptop(id=4, manufacturer="Apple", model="macBook", screen_size_in_inches=13, operating_system="macOS"),
+]
+
+for person in people:
+    possible_laptops = find_possible_laptops(laptops, person)
+    print(f"Possible laptops for {person.name}: {possible_laptops}")
\ No newline at end of file
diff --git a/prep/11.py b/prep/11.py
new file mode 100644
index 00000000..6a3d9bac
--- /dev/null
+++ b/prep/11.py
@@ -0,0 +1,109 @@
+# exercise
+# Write a program which:
+
+# Already has a list of Laptops that a library has to lend out.
+# Accepts user input to create a new Person - it should use the input 
+# function to read a person’s name, age, and preferred operating system.
+# Tells the user how many laptops the library has that have that 
+# operating system.
+# If there is an operating system that has more laptops available, 
+# tells the user that if they’re willing to accept that operating 
+# system they’re more likely to get a laptop.
+# You should convert the age and preferred operating system input from 
+# the user into more constrained types as quickly as possible, and 
+# should output errors to stderr and terminate 
+# the program with a non-zero exit code if the user input bad values.
+
+from dataclasses import dataclass
+from enum import Enum
+from typing import List
+from collections import Counter
+import sys
+
+class OperatingSystem(Enum):
+    MACOS = "macOS"
+    ARCH = "Arch Linux"
+    UBUNTU = "Ubuntu"
+
+@dataclass(frozen=True)
+class Person:
+    name: str
+    age: int
+    preferred_operating_system: OperatingSystem
+
+
+@dataclass(frozen=True)
+class Laptop:
+    id: int
+    manufacturer: str
+    model: str
+    screen_size_in_inches: float
+    operating_system: OperatingSystem
+
+def create_a_new_person() -> Person:
+    add_name = input("What is your name? \n")
+    if not add_name or add_name == "" or len(add_name) > 50:
+        print("Enter a valid name.", file=sys.stderr)
+        sys.exit(1)
+
+    add_age = int(input("What is your age? \n"))
+    if add_age < 0 or add_age > 100:
+        print("Enter a valid age.", file=sys.stderr)
+        sys.exit(1)
+
+    add_os = input("What is your preferred operating system? \n")
+
+    if add_os not in [os.value for os in OperatingSystem]:
+        print("Enter a valid operating system.", file=sys.stderr)
+        sys.exit(1)
+
+    return Person(name=add_name, age=add_age, preferred_operating_system=OperatingSystem(add_os))
+
+
+def find_possible_laptops(laptops: List[Laptop], person: Person) -> List[Laptop]:
+    possible_laptops = []
+    other_laptops = []
+    for laptop in laptops:
+        if laptop.operating_system == person.preferred_operating_system:
+            possible_laptops.append(laptop)
+        else:
+            other_laptops.append(laptop)
+    return possible_laptops, other_laptops
+
+def compare_counts_of_poss_and_others(possible_laptops: List[Laptop], other_laptops: List[Laptop], person: Person) -> None:
+    # counter to get obj
+    other_laptops_counted_as_obj = Counter(laptop.operating_system for laptop in other_laptops)
+    # and here turn to tuple os+count
+    most_common_laptop = other_laptops_counted_as_obj.most_common(1)[0]
+
+    if len(possible_laptops) < most_common_laptop[1]:
+        # print(f"There are more laptops available with {str(most_common_laptop[0])} than your preferred OS {person.preferred_operating_system.value}. Consider accepting that OS to increase your chances of getting a laptop.")
+        print(f"There are more laptops available with {most_common_laptop[0].value} than your preferred OS {person.preferred_operating_system.value}. Consider accepting that OS to increase your chances of getting a laptop.")
+    else:
+        print("Your chosen os has the biggest availability.")
+
+people = [
+    # Person(name="Imran", age=22, preferred_operating_system=OperatingSystem.UBUNTU),
+    # Person(name="Eliza", age=34, preferred_operating_system=OperatingSystem.ARCH),
+]
+
+laptops = [
+    Laptop(id=1, manufacturer="Dell", model="XPS", screen_size_in_inches=13, operating_system=OperatingSystem.ARCH),
+    Laptop(id=2, manufacturer="Dell", model="XPS", screen_size_in_inches=15, operating_system=OperatingSystem.UBUNTU),
+    Laptop(id=3, manufacturer="Dell", model="XPS", screen_size_in_inches=15, operating_system=OperatingSystem.UBUNTU),
+    Laptop(id=4, manufacturer="Apple", model="macBook", screen_size_in_inches=13, operating_system=OperatingSystem.MACOS),
+]
+
+for person in people:
+    possible_laptops = find_possible_laptops(laptops, person)
+    print(f"Possible laptops for {person.name}: {possible_laptops}")
+
+
+def execute():
+    new_person = create_a_new_person()
+    possible_laptops, other_laptops = find_possible_laptops(laptops, new_person)
+    print(f"Number of laptops matching your preferred OS: {len(possible_laptops)}")
+    compare_counts_of_poss_and_others(possible_laptops, other_laptops, new_person)
+
+
+execute()
\ No newline at end of file
diff --git a/prep/12.py b/prep/12.py
new file mode 100644
index 00000000..65584651
--- /dev/null
+++ b/prep/12.py
@@ -0,0 +1,40 @@
+# Play computer with this code. Predict what you expect each line will do.
+#  Then run the code and check your predictions. (If any lines cause 
+#  errors, you may need to comment them out to check later lines).
+
+class Parent:
+    def __init__(self, first_name: str, last_name: str):
+        self.first_name = first_name
+        self.last_name = last_name
+
+    def get_name(self) -> str:
+        return f"{self.first_name} {self.last_name}"
+
+class Child(Parent):
+    def __init__(self, first_name: str, last_name: str):
+        super().__init__(first_name, last_name)
+        self.previous_last_names = []
+
+    def change_last_name(self, last_name) -> None:
+        self.previous_last_names.append(self.last_name)
+        self.last_name = last_name
+
+    def get_full_name(self) -> str:
+        suffix = ""
+        if len(self.previous_last_names) > 0:
+            suffix = f" (née {self.previous_last_names[0]})"
+        return f"{self.first_name} {self.last_name}{suffix}"
+
+person1 = Child("Elizaveta", "Alekseeva")
+print(person1.get_name()) # prints Elizaveta Alekseeva
+print(person1.get_full_name()) # prints Elizaveta Alekseeva
+person1.change_last_name("Tyurina") # no print
+print(person1.get_name()) # prints Elizaveta Tyurina
+print(person1.get_full_name()) # prints Elizaveta Tyurina (née Alekseeva)
+
+person2 = Parent("Elizaveta", "Alekseeva")
+print(person2.get_name()) #print Elizaveta Alekseeva
+print(person2.get_full_name()) #no full name method
+person2.change_last_name("Tyurina") #no change last name method
+print(person2.get_name()) # print Elizaveta Alekseeva
+print(person2.get_full_name()) #no full name method so err
\ No newline at end of file
diff --git a/prep/2.py b/prep/2.py
new file mode 100644
index 00000000..47f64459
--- /dev/null
+++ b/prep/2.py
@@ -0,0 +1,10 @@
+# ✍️exercise
+# Read the above code and write down what the bug is. 
+# How would you fix it?
+
+def double(number):
+    return number * 3
+
+print(double(10))
+
+#Either call it tripple or * 2
\ No newline at end of file
diff --git a/prep/3.py b/prep/3.py
new file mode 100644
index 00000000..177f443f
--- /dev/null
+++ b/prep/3.py
@@ -0,0 +1,43 @@
+# ✍️exercise
+# Do not run the following code.
+
+# This code contains bugs related to types. They are bugs mypy can catch.
+
+# Read this code to understand what it’s trying to do. 
+# Add type annotations to the method parameters and return types of this code. 
+# Run the code through mypy, and fix all of the bugs that show up. 
+# When you’re confident all of the type annotations are correct, and the bugs are fixed, 
+# run the code and check it works.
+
+def open_account(balances, name, amount):
+    balances[name] = amount
+
+def sum_balances(accounts):
+    total = 0
+    for name, pence in accounts.items():
+        print(f"{name} had balance {pence}")
+        total += pence
+    return total
+
+def format_pence_as_string(total_pence):
+    if total_pence < 100:
+        return f"{total_pence}p"
+    pounds = int(total_pence / 100)
+    pence = total_pence % 100
+    return f"£{pounds}.{pence:02d}"
+# File "C:\Users\kkazi\Desktop\cyf\Module-Tools\prep\3.py", line 27, in format_pence_as_string
+   # return f"£{pounds}.{pence:02d}"
+                       #^^^^^^^^^^^
+#ValueError: Unknown format code 'd' for object of type 'float'
+balances = {
+    "Sima": 700,
+    "Linn": 545,
+    "Georg": 831,
+}
+
+open_account(balances, "Tobi", 913) # to solve the float int issue value passed in in pence3.py:35: error: Missing positional argument "amount" in call to "open_account"  [call-arg]
+open_account(balances, "Olya", 713) #3.py:36: error: Missing positional argument "amount" in call to "open_account"  [call-arg]
+
+total_pence = sum_balances(balances)
+total_string = format_pence_as_string(total_pence) # 3.py:39: error: Name "format_pence_as_str" is not defined  [name-defined]
+print(f"The bank accounts total {total_string}")
\ No newline at end of file
diff --git a/prep/4-5.py b/prep/4-5.py
new file mode 100644
index 00000000..77589bd7
--- /dev/null
+++ b/prep/4-5.py
@@ -0,0 +1,33 @@
+# Exercise
+# Add the is_adult code to the file you saved earlier.
+
+# Run it through mypy - notice that no errors are reported - mypy understands that Person has a property named age so is happy with the function.
+
+# Write a new function in the file that accepts a Person as a parameter and tries to access a property that doesn’t exist. 
+# Run it through mypy and check that it does report an error.
+
+class Person:
+    def __init__(self, name: str, age: int, preferred_operating_system: str):
+        self.name = name
+        self.age = age
+        self.preferred_operating_system = preferred_operating_system
+
+imran = Person("Imran", 22, "Ubuntu")
+print(imran.name)
+print(imran.address)
+
+eliza = Person("Eliza", 34, "Arch Linux")
+print(eliza.name)
+print(eliza.address)
+
+def is_adult(person: Person) -> bool:
+    return person.age >= 18
+
+print(is_adult(imran))
+#error means prop does not exist
+
+def get_eye_colour(person: Person):
+    return person.eye_colour
+
+print(get_eye_colour(imran))
+#error in mypy no attribute
\ No newline at end of file
diff --git a/prep/6.py b/prep/6.py
new file mode 100644
index 00000000..fb46bf7b
--- /dev/null
+++ b/prep/6.py
@@ -0,0 +1,9 @@
+# exercise
+# Think of the advantages of using methods instead of free functions. Write them down in your notebook.
+1 makes data and logic more organised
+2 makes it easier to find and reuse code
+3 makes the code more specific and it is easier to understand what it is doing for 
+ a junior/learner like me :)
+4 reduces errors
+
+
diff --git a/prep/7.py b/prep/7.py
new file mode 100644
index 00000000..d510ecc9
--- /dev/null
+++ b/prep/7.py
@@ -0,0 +1,27 @@
+# exercise
+# Change the Person class to take a date of birth 
+# (using the standard library’s datetime.date class) and store it in a 
+# field instead of age.
+
+# Update the is_adult method to act the same as before.
+
+from datetime import date
+
+class Person:
+    def __init__(self, name: str, dob: date, preferred_operating_system: str):
+        self.name = name
+        self.dob = dob
+        self.preferred_operating_system = preferred_operating_system
+        
+
+    def is_adult(self):
+        today = date.today()
+        age = date.today().year - self.dob.year
+        if (today.month, today.day) < (self.dob.month, self.dob.day):
+            age -= 1
+        return age >= 18
+
+imran = Person("Imran", date(1988, 10, 10), "Ubuntu")
+print(imran.is_adult())
+imran = Person("Jay", date(2015, 10, 10), "Ubuntu")
+print(imran.is_adult())
\ No newline at end of file
diff --git a/prep/8.py b/prep/8.py
new file mode 100644
index 00000000..b7b4c8b3
--- /dev/null
+++ b/prep/8.py
@@ -0,0 +1,30 @@
+# ✍️exercise
+# Write a Person class using @datatype which uses a datetime.date 
+# for date of birth, rather than an int for age.
+
+# Re-add the is_adult method to it.
+
+from dataclasses import dataclass
+from datetime import date
+
+@dataclass
+class Person:
+    # def __init__(self, name: str, dob: date, preferred_operating_system: str):
+    #     self.name = name
+    #     self.dob = dob
+    #     self.preferred_operating_system = preferred_operating_system
+    name: str
+    dob: date
+    preferred_operating_system: str    
+
+    def is_adult(self):
+        today = date.today()
+        age = date.today().year - self.dob.year
+        if (today.month, today.day) < (self.dob.month, self.dob.day):
+            age -= 1
+        return age >= 18
+
+imran = Person("Imran", date(1988, 10, 10), "Ubuntu")
+print(imran.is_adult())
+imran = Person("Jay", date(2015, 10, 10), "Ubuntu")
+print(imran.is_adult())
\ No newline at end of file
diff --git a/prep/9.py b/prep/9.py
new file mode 100644
index 00000000..7afa54ab
--- /dev/null
+++ b/prep/9.py
@@ -0,0 +1,25 @@
+# ✍️exercise
+# Fix the above code so that it works. You must not change the print 
+# on line 17 - we do want to print the children’s ages. 
+# (Feel free to invent the ages of Imran’s children.)
+
+from dataclasses import dataclass
+from typing import List
+
+@dataclass(frozen=True)
+class Person:
+    name: str
+    age: int
+    children: List["Person"]
+
+fatma = Person(name="Fatma", age=12, children=[])
+aisha = Person(name="Aisha", age=25, children=[])
+
+imran = Person(name="Imran", age=67, children=[fatma, aisha])
+
+def print_family_tree(person: Person) -> None:
+    print(person.name)
+    for child in person.children:
+        print(f"- {child.name} ({child.age})")
+
+print_family_tree(imran)
\ No newline at end of file
diff --git a/prep/notes.md b/prep/notes.md
new file mode 100644
index 00000000..1887d3d5
--- /dev/null
+++ b/prep/notes.md
@@ -0,0 +1,39 @@
+
+def how_many_laptops_match_os(person: Person) -> List[Laptop]:
+    possible_laptops = []
+    for laptop in laptops:
+        if laptop.operating_system == person.preferred_operating_system:
+            possible_laptops.append(laptop)
+    prinet(f"Number of laptops matching your preferred OS: {len(possible_laptops)}")
+    return possible_laptops
+
+
+# for person in people:
+#     possible_laptops = find_possible_laptops(laptops, person)
+#     print(f"Possible laptops for {person.name}: {possible_laptops}")
+
+#  If there is an operating system that has more laptops available, 
+# tells the user that if they’re willing to accept that operating 
+# system they’re more likely to get a laptop.
+
+def get_counts_of_all_laptops_by_os(laptops: List[laptop]) -> dict:
+    number_of_laptops = {}
+
+    for laptop in laptops:
+        particular_os = laptop.operating_system
+        
+        if particular_os in number_of_laptops:
+            number_of_laptops[particular_os] += 1
+        else:
+            number_of_laptops[particular_os] = 1
+            
+    return number_of_laptops
+
+def check_if_there_is_os_with_more_laptops(laptops: List[Laptop], person: Person, possible_laptops: List[Laptop]) -> None:
+    not_matching_laptop_counts = get_counts_of_all_laptops_by_os(laptops)
+
+
+    for laptop in get_counts_of_all_laptops_by_os(laptops):
+        if laptop.operating_system != person.preferred_operating_system:
+            not_matching_laptop_counts = get_counts_of_all_laptops_by_os(laptops)
+    print(f"There are more laptops available with {laptop.operating_system.value} than your preferred OS {person.preferred_operating_system.value}. Consider accepting that OS to increase your chances of getting a laptop.")
diff --git a/sprint 5/laptop.py b/sprint 5/laptop.py
new file mode 100644
index 00000000..83eb3852
--- /dev/null
+++ b/sprint 5/laptop.py	
@@ -0,0 +1,50 @@
+In the prep, there was an exercise around finding possible laptops for a group of people.
+
+Your exercise is to extend this to actually allocate laptops to the people.
+
+Given these class definitions:
+
+from dataclasses import dataclass
+from enum import Enum
+from typing import List
+
+class OperatingSystem(Enum):
+    MACOS = "macOS"
+    ARCH = "Arch Linux"
+    UBUNTU = "Ubuntu"
+
+@dataclass(frozen=True)
+class Person:
+    name: str
+    age: int
+    # Sorted in order of preference, most preferred is first.
+    preferred_operating_system: List[OperatingSystem]
+
+
+@dataclass(frozen=True)
+class Laptop:
+    id: int
+    manufacturer: str
+    model: str
+    screen_size_in_inches: float
+    operating_system: OperatingSystem
+Write a function with this signature:
+
+def allocate_laptops(people: List[Person], laptops: List[Laptop]) -> Dict[Person, Laptop]:
+Every person should be allocated exactly one laptop.
+
+If we define "sadness" as the number of places down in someone's ranking the 
+operating system the ended up with (i.e. if your preferences were [UBUNTU, ARCH, MACOS] 
+
+and you were allocated a MACOS machine your sadness would be 2), we want to minimise the total sadness of 
+all people. If we allocate someone a laptop with an operating system not in their preferred list, treat 
+them as having a sadness of 100.
+
+def ranking():
+    
+
+def minimize_sandess():
+
+
+def allocate_laptops():
+    
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