How does this code know to use the key of a dictionary

[scidam]

My question is, how does the program know that I want the key returned from the variable account? How could I use the key and return the value?

if you enter in the command line python password.py email,
the 'account' variable (line #11) will be set to email (a string). Further, the program checks if the record named 'email' exists in PASSWORD dictionary and tries to get corresponding password for the account (email): PASSWORD[account]. pyperclip.copy is copying the value of password (in case of 'email' account it would be 'incospmei#$%') to clipboard. Finally, you get information that password was copied (line #15). Hope that helps.