def log_in(event):
'''Function to log in to the banking system using a known account number and PIN.'''
global account
global pin_number_var
global account_number_var
read = event + '.txt'
# Create the filename from the entered account number with '.txt' on the end
# Try to open the account file for reading
accept_loging = False
try:
with open(str(read),
'r') as account_file: # Open the account file for reading
account_number = account_file.readline(
)[:-1] # First line is account number
account_pin = account_file.readline(
)[:
-1] # Second line is PIN number, raise exceptionk if the PIN entered doesn't match account PIN read
if account_pin != pin_number_var.get():
raise ValueError("Pin doesnt match")
else:
accept_loging = True
account_balance = float(account_file.readline(
)[:-1]) # Read third and fourth lines (balance and interest rate)
account_interest = float(account_file.readline()[:-1])
transaction_list = []
# Section to read account transactions from file - start an infinite 'do-while' loop here
# Attempt to read a line from the account file, break if we've hit the end of the file. If we
# read a line then it's the transaction type, so read the next line which will be the transaction amount.
# and then create a tuple from both lines and add it to the account's transaction_list
while True:
_type = account_file.readline()[:-1] # Attempt to read a line
if not _type: # If we failed, then exit
break
_amount = float(account_file.readline()[:-1])
transaction_list.append((_type.strip(), _amount))
account.account_number = account_number
account.account_pin = account_pin
account.balance = account_balance
account.account_interest = account_interest
account.transaction_list = transaction_list
# Close the file now we're finished with it (context manager is doing this for us)
except ValueError:
messagebox.showerror("Error", "Incorrect PIN")
account = BankAccount()
account.account_interest = .30
account = account_number_var
clear_pin_entry("event")
account_number_entry.focus_force()
except Exception:
# Catch exception if we couldn't open the file or PIN entered did not match account PIN
messagebox.showerror("Error", "file doesnt exists")
account = BankAccount()
clear_pin_entry("event")
account_number_entry.focus_force()
# Show error messagebox and & reset BankAccount object to default...
# ...also clear PIN entry and change focus to account number entry
if accept_loging:
remove_all_widgets()
create_account_screen()
