[Python] fixed rate mortgage in Python

I'm relatively new to coding. I have a task where I have to program an fixed rate mortgage calculator in python. I started by coding this:

import pandas as pd
import numpy_financial as npf
from datetime import date

interest = 0.025
years = 10
payments_year = 12
mortgage = 1500000
start_date = (date(2021, 1, 1))

rng = pd.date_range(start_date, periods=years * payments_year, freq='MS')
rng.name = "Payment Date"
df = pd.DataFrame(index=rng, columns=['Payment', 'Principal Paid', 'Interest Paid', 'Ending Balance'], dtype='float')
df.reset_index(inplace=True)
df.index += 1
df.index.name = "Period"

df["Payment"] = -1 * npf.pmt(interest/12, years*payments_year,mortgage)
df["Interest Paid"] = -1 * npf.ipmt(interest/payments_year, df.index, years*payments_year,mortgage)
df["Principal Paid"] = -1 * npf.ppmt(interest/payments_year, df.index, years*payments_year,mortgage)
df["Ending Balance"] = 0
df.loc[1, "Ending Balance"] = mortgage - df.loc[1, "Principal Paid"]
df = df.round(2)

for period in range(2, len(df)+1):
previous_balance = df.loc[period-1, "Ending Balance"]
principal_paid = df.loc[period, "Principal Paid"]

if previous_balance == 0:
df.loc[period, ['Payment', 'Principal Paid', 'Interest Paid', 'Ending Balance']] == 0
continue
elif principal_paid <= previous_balance:
df.loc[period, "Ending Balance"] = previous_balance - principal_paid

print(df)


I have created variables with specific numbers, and as a result got table. I want the calculator itself to come out as a table.

But I also want to use input, so the user can enter the loan amount, interest rate, start date for loan, etc. instead of having a specific variable. Just some simple input like this here:

loan = input("Write the amount you want to loan \n")
loan = float(loan)

start_date = input("What is the starte date, put it in YYYY-MM-DD format")
year, month, day = map(int, start_date.split("-"))
date = datetime.date(year, month, day)


How can I combine the input numbers and still get a table? Appreciate help and tips!

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