Importing functions that require parameters

[Matt_D]

Good afternoon.

As a self-tutoring project I am writing a one-time-pad encrypt/decrypt
script. I have completed the encryption portion and am working
currently on the decryption algorithm. My goal is to have the encrypt
and decrypt be individual modules vice two parts of the same.

My problem, or perhaps more accurately, question, lies in importing a
function from the otp_encrypt script. Here is the function I am
attempting to call:

def get_key(ptext):
    """Convert one-time-pad to uppercase, and strip spaces. On final
line slice pad to match length of plain text. (OTP will not work if
len(pad) != len(plaintext)"""
    ptext = upper_case(ptext)
    otp = # key removed just due to sheer length
    otp = string.upper(otp)
    new = ""
    for letter in otp:
        if letter in string.uppercase:
            new += letter
    return new[:len(ptext)]

The parameter of get_key is sys.argv[1]. Now I understand why I'm
getting the errors I'm getting (invalid syntax if I include () or
([parameter], or an IndexError if I don't include those), but my
question is, is it feasible to import a function from a module when
that function requires a parameter from elsewhere in the imported
module? Or is it just better to just import * in all cases?