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How to pass user inputs to an object of a class?

This code is a Simple Student Management System in which I want it to receive inputs from the user and display according to the call. I have created a class Student and initialized the variables. I created a method accept(self) for receiving the user inputs and appending the details to a list of dictionaries. But I am stuck on how I can initialize the inputs that I have received. How can I call the methods outside of class Student since I am unable to create an object for class Student? I am a beginner in Python. Having a hard time understanding OOP. Please help me!
Here is the code I wrote:
class Student:
student_details = []
def __init__(self, name, rollno, mark1, mark2):
self.name = name
self.rollno = rollno
self.mark1 = mark1
self.mark2 = mark2
def accept(self):
no_of_entries = int(input("Enter the number of entries: "))
i = 1
while i <= no_of_entries:
print(f"Student {i}")
name = input("Name: ")
rollno = int(input("Roll: "))
mark1 = int(input("Mark 1: "))
mark2 = int(input("Mark 2: "))
Student(name, rollno, mark1, mark2).student_details.append({
"Name": self.name,
"Rollno": self.rollno,
"Mark1": self.mark1,
"Mark2": self.mark2,
})
print()
i += 1
print(Student.student_details)
student1 = Student()
proceed = True
while proceed:
print("STUDENT MANAGEMENT SYSTEM".center(50, '-'))
print()
print("* Accept Student entries (1): ")
print("* Search Student entries (2): ")
print("* Update Student entries (3): ")
print("* Delete Student entries (4): ")
print("* Display Student entries (5): ")
choice = int(input("Enter your choice: "))
if choice == 1:
I get the error:
Student.__init__() missing 4 required positional arguments: 'name', 'rollno', 'mark1', and 'mark2'
I don't know what to do. Even this is the problem I am facing with OOP in Python. If anyone can help me with this than I will be grateful

EDIT: The callback comes from the student1 = Student()
delete the statement and declare the accept method as a static method.
Then you can deklare a student in the method and can appent the student.
Your mistake should be here:
Student(name, rollno, mark1, mark2).student_details.append({
"Name": self.name,
"Rollno": self.rollno,
"Mark1": self.mark1,
"Mark2": self.mark2,
})
You try to initialise a object and then you try to use it as a dict.
st1 = Student(name, rollno, mark1, mark2)
Student.student_details.append(st1)
Also you can use a classattribut in a object but the changes will only be present in the object. It wouldnt be in all object.
It would be best make the method accept in a function or you will end up with many object with the same values.
If you want to leave it as a method you can change the code to:
Student.student_details.append(self)

By default methods defined in a Python class are instance methods, so they need to be called on an already-existing object instance. If you want to create a custom constructor, the method should be probably marked as a class method by using #classmethod decorator, so it can be called on the class itself.
class Student:
student_details = []
def __init__(self, name, rollno, mark1, mark2):
self.name = name
self.rollno = rollno
self.mark1 = mark1
self.mark2 = mark2
#classmethod
def accept(cls):
no_of_entries = int(input("Enter the number of entries: "))
for i in range(no_of_entries):
print(f"Student {i}")
name = input("Name: ")
rollno = int(input("Roll: "))
mark1 = int(input("Mark 1: "))
mark2 = int(input("Mark 2: "))
student = cls(name, rollno, mark1, mark2)
cls.student_details.append(student)
print(cls.student_details)
Student.accept()

student1 = Student()
you need to pass 4 parameters here
def __init__(self, name, rollno, mark1, mark2):
So you should have
student1 = Student('name', 'rollno', 'mark1', 'mark2')
or something

You forgot to put arguments when you call that class.
For example:
student1 = Student(name='a', rollno='0', mark1='1', mark2='2')
I'm not sure what your objective is. If you just want to input student information into a list, maybe the code below can give you an idea.
class Student:
student_details = []
def __init__(self, name, rollno, mark1, mark2):
self.name = name
self.rollno = rollno
self.mark1 = mark1
self.mark2 = mark2
student_list = []
print("STUDENT MANAGEMENT SYSTEM".center(50, '-'))
print()
print("* Accept Student entries (1): ")
print("* Search Student entries (2): ")
print("* Update Student entries (3): ")
print("* Delete Student entries (4): ")
print("* Display Student entries (5): ")
choice = int(input("Enter your choice: "))
if choice == 1:
print("You have selected (1) - Accept Student entries")
no_of_entries = int(input("Enter the number of entries: "))
for i in range(0, no_of_entries):
print("Input student no", i+1, "information.")
student = Student(name=input("Name: "), rollno=input("Roll: "), mark1=input("Mark 1: "), mark2=input("Mark 2: "))
student_list.append(student)
elif choice == 2:
pass
elif choice == 3:
pass
elif choice == 4:
pass
elif choice == 5:
pass
else:
print("Invalid choice.")

Problem with referring to methods in classes in python

i have this code:
class Contact:
def __init__(self, name, phone):
Contact.name = name
Contact.phone = phone
class AddContact:
def __init__(self):
self.People = []
def add_people(self, x):
self.People.append(x)
def print_contact(self):
for x in self.People:
print("name:" + x.name)
print("phone:", x.phone)
while True:
print("----MENU----")
print("1 -> add contact")
print("2 -> contact list")
choice = int(input("enter your choice: "))
if choice == 1:
name = input("enter the name of the contact: ")
phone = input("enter the phone number of the contact: ")
person = Contact(name, phone)
AddContact.add_people(person)
if choice == 2:
AddContact.print_contact()
what im trying to make is a contact book where the user can add and view all of his contacts, ive recently learned classes and thought this was the correct way to make it but i get issues the erros im getting is that the parameters x and self are unfilled on this line:
def add_people(self, x):
when i call them below outside of the class, ive been trying but i dont understand the problem and would like some assistance.
thanks is advance.

You are using AddContact wrong. You need to create an instance of it (just like you created an instance of Contact).
While we are at it, PhoneBook would be a much better name for this class.
...
class PhoneBook:
def __init__(self):
self.People = []
def add_people(self, x):
self.People.append(x)
def print_contact(self):
for x in self.People:
print("name:" + x.name)
print("phone:", x.phone)
phone_book = PhoneBook()
while True:
print("----MENU----")
print("1 -> add contact")
print("2 -> contact list")
choice = int(input("enter your choice: "))
if choice == 1:
name = input("enter the name of the contact: ")
phone = input("enter the phone number of the contact: ")
person = Contact(name, phone)
phone_book.add_people(person)
if choice == 2:
phone_book.print_contact()

ValueError: not enough values to unpack (expected 3, got 2) & TypeError: must be str, not MemberClass

Below is my code for a class I am currently working. The title contains the errors I am receiving. Could someone please assist with my code? (The comment's explain the area of concern. Main Menu functions 5 & 6.)
PART 1 - CLASS ESTABLISHMENT
class MemberClass:
name = ""
phone = 0
number = 0
# Initiator Method
def __init__(self, name, phone, number):
self.name = name
self.phone = phone
self.number = number
# Mutator Method 1
def set_name(self, name):
self.name = name
# Mutator Method 2
def set_phone(self, phone):
self.phone = phone
# Mutator Method 3
def set_number(self, number):
self.number = number
# Accessor Method 1
def get_name(self):
return self.name
# Accessor Method 2
def get_phone(self):
return self.phone
# Accessor Method 3
def get_number(self):
return self.number
# Display Method
def display_data(self):
print("")
print("Current Team Member's Information")
print("------------------------------------------------")
print("Member's Name: ", self.name)
print("Member's Phone Number: ", self.phone)
print("Member's Jersey Number: ", self.number)
print("------------------------------------------------")
PART 2 - PROGRAM FUNCTIONS AND DATA
# Create a function for the main menu
def print_menu():
print("===========Main Menu===========")
print("1. Display Current Team Roster.")
print("2. Add Member.")
print("3. Remove Member.")
print("4. Edit Member.")
print("5. Save Progress.")
print("6. Load Current Team Roster")
print("9. Exit Program.\n")
return int(input("Please Enter Your Selection: "))
# Create a function for main menu option 1
def print_members(team_members):
if len(team_members) == 0:
print("No Current Team Members In Memory! Please Add All Team Members.")
else:
for x in team_members.keys():
team_members[x].display_data()
# Create a function for main menu option 2
def add_members(team_members):
new_name = input("Enter New Team Member's Name: ")
new_phone = int(input("Enter New Team Member's Phone Number: "))
new_number = int(input("Enter New Team Member's Jersey Number: "))
team_members[new_name] = MemberClass(new_name, new_phone, new_number)
return team_members
# Create a function for main menu option 3
def remove_members(team_members):
remove_name = input("Enter Existing Team Member's Name to Remove: ")
if remove_name in team_members:
del team_members[remove_name]
print("The Team Member ("+remove_name+") Is No Longer In Our Roster.")
else:
print("The Provided Name ("+remove_name+") Is Not Currently In Our Roster. Please Try Again.")
return team_members
# Create a function for main menu option 4
def edit_members(team_members):
original_name = input("Enter Existing Team Member's Name To Edit: ")
if original_name in team_members:
adjusted_name = input("Enter Existing Team Member's Updated Name: ")
adjusted_phone = int(input("Enter Existing Team Member's Updated Phone Number: "))
adjusted_number = int(input("Enter Existing Team Member's Updated Jersey Number: "))
del team_members[original_name]
team_members[original_name] = MemberClass(adjusted_name, adjusted_phone, adjusted_number)
else:
print("The Provided Name ("+original_name+") Is Not Currently In Our Roster. Please Try Again.")
return team_members
# Create a function for main menu option 5 ***PROBLEM AREA***
def save_members(members, filename):
out_file = open(filename, "wt")
with open(filename, "wt") as out_file:
for name, phone, number in members.items():
out_file.write(name + "," + phone + "," + number + "\n")
# Create a function for main menu option 6 ***PROBLEM AREA***
def load_members(members, filename):
in_file = open(filename, "rt")
with open(filename, "rt") as in_file:
while True:
in_line = in_file.readline()
if not in_line:
break
in_line = in_line[:-1]
name, phone, number = in_line.split(",")
members[name] = phone
PART 3 - PROGRAM ROOT CODE
# Team manager welcome screen, date & time
print("Welcome to San Angelo's Softball Team Roster")
print("This program keeps the most up-to-date information")
print("Today's Date: April 23, 2018")
print("Current Time: 0900\n")
# Create a dictionary named "team_members"
team_members = {}
# Provides Menu Screen
menu_selection = print_menu()
# Create while loop repeating the main menu.
while menu_selection != 9:
if menu_selection == 1:
print_members(team_members)
elif menu_selection == 2:
team_members = add_members(team_members)
elif menu_selection == 3:
team_members = remove_members(team_members)
elif menu_selection == 4:
team_members = edit_members(team_members)
elif menu_selection == 5:
filename = input("Enter Desired Filename: ")
save_members(team_members, filename)
elif menu_selection == 6:
filename = input("Enter Existing Filename: ")
load_members(team_members, filename)
menu_selection = print_menu()
print("Thank You For Updating San Angelo's Softball Team Roster!")

When you iterate a dictionary via dict.items, you may only iterate key / value pairs. Therefore, this line will fail as you are attempting to unpack 3 items when only 2 exist (key & value):
for name, phone, number in members.items():
Instead, what you should do:
for name, myclass in members.items():
phone = myclass.phone
number = myclass.number

How to delete an item from a class in python based on user input?

I am trying to allow a member to leave the Team if they so wish. By doing this, the system will delete them and their user ID will become available to the next person who wishes to join the team. I am receiving an error with my code. Can someone please advise what I am doing wrong and how this can be achieved?
I would like my add members and remove members to update all the time, based on user input and the needs of the members. I hope this makes sense!
For example: If 'Carl' decided to leave, he would be removed and the next member to join would be assigned the membership ID '2'
Below is my code:
all_users = []
class Team(object):
members = []
user_id = 0
def __init__(self, first, last, address):
self.user_id = Team.user_id
self.first = first
self.last = last
self.address = address
self.email = first + '.' + last + '#python.com'
Team.user_id += 1
Team.members.append(self)
def __str__(self):
print()
return 'Membership ID: {}\nFirst Name: {}\nSurname: {}\nLocation: {}\nEmail: {}\n'.format(self.user_id,
self.first, self.last,
self.address,
self.email)
print()
#staticmethod
def all_members():
for user in all_users:
print(user)
#staticmethod
def add_member():
print()
print("Welcome to the team!")
print()
first_name = input("What's your first name?\n")
second_name = input("What's your surname?\n")
address = input("Where do you live?\n")
all_users.append(Team(first_name, second_name, address))
#staticmethod
def remove_member():
print()
print("We're sorry to see you go , please fill out the following information to continue")
print()
first_name = input("What's your first name?\n")
second_name = input("What's your surname?\n")
address = input("Where do you live?\n")
unique_id = input("Finally, what is your User ID?\n")
if unique_id in all_users:
del unique_id
all_users(User(first_name, second_name, address))
def main():
user_1 = Team('Chris', 'Parker', 'London')
user_2 = Team('Carl', 'Lane', 'Chelsea')
all_users.extend([user_1, user_2])
continue_program = True
while continue_program:
print("1. View all members")
print("2. Want to join the team?")
print("3. Need to leave the team?")
print("3. Quit")
try:
choice = int(input("Please pick one of the above options "))
if choice == 1:
Team.all_members()
elif choice == 2:
Team.add_member()
elif choice == 3:
Team.remove_member()
elif choice == 4:
continue_program = False
print()
print("Come back soon! ")
print()
else:
print("Invalid choice, please enter a number between 1-3")
main()
except ValueError:
print()
print("Please try again, enter a number between 1 - 3")
print()
if __name__ == "__main__":
main()

The remove_member method is wrong for several reasons. The line del unique_id will not remove the value from all_users, which is just a list of Team Members. And you shouldn't have to ask the user for all of this information - just the ID (or the name) would be enough.
What I suggest is:
#staticmethod
def remove_member():
print()
print("We're sorry to see you go , please fill out the following information to continue")
print()
unique_id = input("what is your User ID?\n")
unique_id = int(unique_id)
for i, user in enumerate(all_users):
if user.user_id == unique_id:
all_users.remove(i)
break

If it is important that the user ids are reused, you can keep a list of user ids that are available again. When creating a new member, you can first check that list, and use an old id if there is one.
You can also choose not to reuse the user ids of removed users. An id doesn't really have a meaning and not reusing it makes it simpeler for you.
Finally, you might want to restructure your code:
Team(first_name, second_name, address)
This doesn't make sense: a team with a first name, last name and adress! Better would be to have two classes:
team = Team()
user = User(first_name, second_name, address)
team.add_member(user)
team.remove_member(user)
Some other tips:
# This won't work, because all_users contains Team instances, not numbers. So the user will never be found.
if unique_id in all_users:
# This won't do anything: `del` only removes the access to the variable (might free up memory in heavy applications). It doesn't remove the user from all_users
del unique_id

Python 3 - Cant get data to display when called

This is the function defined in class "Roster"
class Roster:
def __init__(self, name, phone, jersy):
self.name = name
self.phone = phone
self.jersy = jersy
def setName(self, name):
self.name = name
def setPhone(self, phone):
self.phone = phone
def setnumber(self, jersy):
self.number = jersy
def getName(self):
return self.name
def getPhone(self):
return self.phone
def getNumber(self):
return self.jersy
def displayMenu(self):
print ("==========Selection Menu==========")
print ("1. Display the Roster")
print ("2. Add a Player to the Roster")
print ("3. Remove a Player from the Roster")
print ("4. Change a Player Name displayed in the Roster")
print ("5. Load the Roster")
print ("6. Save the Roster")
print ("7. Quit")
print ()
return int (input ("Selection>>> "))
def displayRoster(self):
print ("****Team Roster****")
print ("Player's Name:", self.name)
print ("Player's Telephone number:", self.phone)
print ("Player's Jersey number:", self.jersy)
This is the code:( I understand that you don't have to "Import" a class into itself so there is no Import call)
Players = {}
def addPlayer(Players):
newName = input ("Add a player's Name: ")
newPhone = input ("Phone number: ")
newNumber = input ("Jersey number: ")
Players[newName] = newName, newPhone, newNumber
return Players
def removePlayer(Players):
removeName = input ("What name would you like to remove? ")
if removeName in Players:
del Players[removeName]
else:
print ("Name was not found!")
return Players
def editPlayer(Players):
oldName = input ("What name would you like to change? ")
if oldName in Players:
newName = input ("What is the new name? ")
newPhone = input ("Phone number: ")
newNumber = input ("Jersey number: ")
Players[newName] = newName, newPhone, newNumber
del Players[oldName]
print ("***", oldName, "has been changed to", newName)
else:
print ("Name was not found!")
return Players
def saveRoster(Players):
print("Saving data...")
outFile = open("D:\Documents\Grantham\Python Projects\Python Week Six\Roster.txt", "wt")
for x in Players.keys():
name = Roster.getName(Players)
phone = Roster.getPhone(Players)
jersy = Roster.getNumber(Players)
outFile.write("name+","+phone+","+jersy+","\n")
print("Data saved.")
outFile.close()
return Players
def loadRoster():
Players = {}
filename = input("Filename to load: ")
inFile = open(Filename(Players), "rt")
print("Loading data...")
while True:
inLine = inFile.readline()
if not inLine:
break
inLine = inLine[:-1]
name, phone, jersy = inLine.split(",")
Players[name] = RosterClass.Players(name, phone, jersy)
print("Data Loaded Successfully.")
inFile.close()
return Players
print ("Welcome to the Team Manager")
menuSelection = Roster.displayMenu ('Players')
while menuSelection != 7:
if menuSelection == 1:
myRoster.displayRoster (Players)
elif menuSelection == 2:
Players = addPlayer (Players)
elif menuSelection == 3:
Players = removePlayer (Players)
elif menuSelection == 4:
Players = editPlayer (Players)
elif menuSelection==5:
loadRoster(Players)
elif menuSelection==6:
saveRoster(Players)
menuSelection = Roster.displayMenu (Players)
print ("Exiting Program...")
I keep getting this error:
Traceback (most recent call last):
File ".idea/Adv Team Roster.py", line 108, in <module>
Roster.displayRoster ('Players')
File ".idea/Adv Team Roster.py", line 39, in displayRoster
print ("Player's Name:", self.name)
AttributeError: 'str' object has no attribute 'name'
I'm also having problems with the save/load routine but that's another post.

Your code has a number of conceptual problems that you need to solve before you can start trying to run it and start asking for help with compiler errors. Here are three, to get you started.
(1) Your Roster class is designed to be instantiated, but you never create an instance. Whenever you write a class, among the early questions you should ask yourself are, "What code will create instances of this class? Under what circumstances? How will that code get the data it needs to create an instance? What will that code do with the instance right after it has created the instance?"
(2) Your Roster class is misnamed, which is probably confusing you. A roster is a list of players. Your Roster is data about a single player. I recommend renaming Roster to Player, creating some data structure (like your current Players) called roster to hold a bunch of players, and then following the consequences of that change.
(3) Once you have a clear idea of what rosters and players are, you can ask questions like, "Where will I store rosters and players? How will I pass them around to different parts of my code? What functionality should be associated with a roster? with a player? with the top level of my code? with other entities that I haven't thought about yet?"
After all that thinking, you might come the conclusion that displayPlayer should be a function on the Player class and that you therefore need to rename displayRoster to displayPlayer. Since you will have created instances of Player, perhaps one called myplayer (that's just an example name), you will now be able to say myplayer.displayPlayer(), and Python will run the displayPlayer code with self automatically set to the myplayer instance. At that point the compiler error you are complaining about will disappear, not because you "fixed" it, but because it naturally goes away once you are thinking clearly about your system.
And in general, that is the way to think about compiler errors: If it's not immediately obvious how to fix it, then it's probably a sign that you aren't thinking clearly about your system, so you need to take a step back and think about higher-level problems than the specific error.