how can i keep/ save the user input in dictionary? - python-3.x

Question

import pandas as pd
from pandas import DataFrame
words = {}
def add_word():
ask = input("Do You Want To Add a New Word?(y/n): ")
if ask == 'y':
new_word = input("type the word you want to add: ")
word_meaning = input("type the word meaning: ")
words[new_word] = [word_meaning]
elif ask == 'n':
pass
add_word()
table = pd.DataFrame(data=words)
table_transposed = table.transpose()
print(table_transposed)
as you can see, i want to make a dictionary but i don't know how to save the user's input.
i want to take the user input and save it in the dictionary, so the next time he uses the program he can see everything he added before

Answer 1

When you make and populate (fill) a dictionary in a running Python program, that dictionary only exists as long as the program is running. When you close the program - that memory is wiped and any modifications that are made are not stored.
As Tomerikoo pointed out, this solution: shelving dictionaries will allow you to preserve your dictionary after the program is closed.
I copy the code from the link (jabaldonedo's solution) and annotate it for you for clarity.
import shelve # this is a Python library that allows you to store dictionaries after the program is closed
data = {'foo':'foo value'} # this is a mock-up dictionary. "words" in your case
d = shelve.open('myfile.db') # this creates a storage container in the program folder that can store multiple dictionaries. You can see this file appear when this code runs.
d['data'] = data # you make a section in that storage container, give it a name, e.g. "data" in this case, and store your dictionary in that section. You will store your "words" here.
d.close() # close the storage container if you do not intend to put anything else inside.
When you close and open up the program, the dictionary will not automatically pop into your running memory - you need to write code to access it. It can be made as an option in your game menu, e.g. "Load existing dictionary of words".
Back to jabaldonedo's solution:
import shelve # no need to import again, if you are writing in the same python program, this is for demonstration
d = shelve.open('myfile.db') # open the storage container where you put the dictionary
data = d['data'] # pull out the section, where you stored the dictionary and save it into a dictionary variable in the running program. You can now use it normally.
d.close() # close the storage container if you do not intend to use it for now.
EDIT: Here is how this could be used in the specific context provided in your answer. Note that I imported an additional library and changed the flags in your shelve access commands.
As I mentioned in my comment, you should first attempt to load the dictionary before writing new things into it:
import shelve
import dbm # this import is necessary to handle the custom exception when shelve tries to load a missing file as "read"
def save_dict(dict_to_be_saved): # your original function, parameter renamed to not shadow outer scope
with shelve.open('shelve2.db', 'c') as s: # Don't think you needed WriteBack, "c" flag used to create dictionary
s['Dict'] = dict_to_be_saved # just as you had it
def load_dict(): # loading dictionary
try: # file might not exist when we try to open it
with shelve.open('shelve2.db', 'r') as s: # the "r" flag used to only read the dictionary
my_saved_dict = s['Dict'] # load and assign to a variable
return my_saved_dict # give the contents of the dictionary back to the program
except dbm.error: # if the file is not there to load, this error happens, so we suppress it...
print("Could not find a saved dictionary, returning a blank one.")
return {} # ... and return an empty dictionary instead
words = load_dict() # first we attempt to load previous dictionary, or make a blank one
ask = input('Do you want to add a new word?(y/n): ')
if ask == 'y':
new_word = input('what is the new word?: ')
word_meaning = input('what does the word mean?: ')
words[new_word] = word_meaning
save_dict(words)
elif ask == 'n':
print(words) # You can see that the dictionary is preserved between runs
print("Oh well, nothing else to do here then.")

Answer 2

import shelve
words = {}
def save_dict(words):
s = shelve.open('shelve2.db', writeback=True)
s['Dict'] = words
s.sync()
s.close()
def load_dict():
s = shelve.open('shelve2.db', writeback=True)
dict = s['Dict']
print(dict)
s.close()
ask = input('Do you want to add a new word?(y/n): ')
if ask == 'y':
new_word = input('what is the new word?: ')
word_meaning = input('what does the word mean?: ')
words[new_word] = word_meaning
save_dict(words)
elif ask == 'n':
load_dict()
so this is my code after making the save_dict and load_dict functions, it works fine but when i run the program and write a new_word and word_meaning it overwrites the previous data, i believe i am missing something in the save_dict function, if you can point the problem to me i would be so grateful