Run python script from Python Shell with parameters - oop

Question

Disclaimer: I'm trying to write one of my first classes in python, so please make any criticism constructive please.
#!/usr/bin/python
from optparse import OptionParser
class Permutate:
email_dict = {}
email_provider = (
'#gmail.com',
'#aol.com',
'#yahoo.com'
)
def __init__(self, fname, lname):
'''
vars:
[fname] - first name of the permutation
[lname] - last name of the permutation
[email_combination] - first and last name
'''
self.fname = fname
self.lname = lname
self.email_combination = email_combination
'''
compute_first_last():
email_combination = <string> + <string> + <string>
computes the first name and last name combination plus and email provider.
Loop through all combinations of first + last + email_provider while the value *is u
A single combination looks like <fname>.<lname>#<email_provider>
Thank you

Answer 1

After the revisions to the question, this is a working piece of code that will give you output. Not sure if it is exactly what you want, but it will work.
#!/usr/bin/python
from optparse import OptionParser
class Permutate:
email_dict = {}
email_provider = (
'#gmail.com',
'#aol.com',
'#yahoo.com'
)
def __init__(self, fname, lname):
'''
vars:
[fname] - first name of the permutation
[lname] - last name of the permutation
[email_combination] - first and last name
'''
assert isinstance(fname, str) and isinstance(lname, str), "Only strings may be supplied as names"
self.fname = fname
self.lname = lname
self.email_combination = fname + "." + lname
for provider in Permutate.email_provider:
print "%s%s" % (self.email_combination, provider)
def compute_first_last():
'''
compute_first_last():
email_combination = <string> + <string> + <string>
computes the first name and last name combination plus and email provider.
Loop through all combinations of first + last + email_provider while the value *is u
A single combination looks like <fname>.<lname>#<email_provider>
'''
parser = OptionParser(usage='%prog -f fname -l lname', version='%prog 1.1')
parser.add_option('-f', '--fname', dest='fname')
parser.add_option('-l', '--lname', dest='lname')
(opt, args) = parser.parse_args()
perm = Permutate(opt.fname, opt.lname)
if __name__ == '__main__':
compute_first_last()

Answer 2

The optparse library is fairly convenient for accepting command line arguments in Python.
For more information, take a look at:
https://docs.python.org/2/library/optparse.html
You can accept command line arguments similar to that below:
from optparse import OptionParser
def main():
parser = OptionParser(
usage='%prog -f firstname -l lastname',
version='%prog 1.1')
parser.add_option('-f', '--firstname', dest='firstname')
parser.add_option('-l', '--lastname', dest='lastname')
(opt, args) = parser.parse_args()
print opt.firstname
print opt.lastname
# You can create the new Permutate object here
# perm = Permutate(opt.firstname, opt.lastname)
# and call its relevant functions
if __name__ == '__main__':
main()
The results you will get will look like:
python myfile.py -f firstnamehere -l lastnamehere
firstnamehere
lastnamehere
Note: You should also perform input sanitation to ensure that the user is calling the script correctly.

Answer 3

I believe this section and the method compute_first_last():
if __name__ == '__compute_first_last__':
compute_first_last()
should not be within the scope of the Class permutate, which it currently is. Edit: Also, and this part I deleted previously but forgot to re-include, this should actually say:
if __name___ == '__main__':
compute_first_last()
Currently all the interpreter is doing is parsing a file containing a Class. It is missing the execution of the method you want, because it is contained within the class and never called explicitly. Also, you are calling the method compute_first_last supplying no parameters, although it is expecting four. You can take it from here! :-)
Edit: Explanation on how/what this does: What does if __name__ == "__main__": do?
Edit: having checked your code again, I've edited the above.
#!/usr/bin/python
from optparse import OptionParser
class Permutate:
email_dict = {}
email_provider = (
'#gmail.com',
'#aol.com',
'#yahoo.com'
)
def __init__(self, fname, lname):
'''
vars:
[fname] - first name of the permutation
[lname] - last name of the permutation
[email_combination] - first and last name
'''
self.fname = fname
self.lname = lname
self.email_combination = email_combination
'''
compute_first_last():
email_combination = <string> + <string> + <string>
computes the first name and last name combination plus and email provider.
Loop through all combinations of first + last + email_provider while the value *is u
A single combination looks like <fname>.<lname>#<email_provider>
'''
def compute_first_last(self, fname, lname, email_combination):
parser = OptionParser(usage='%prog -f fname -l lname', version='%prog 1.1')
parser.add_option('-f', '--fname', dest='fname')
parser.add_option('-l', '--lname', dest='lname')
(opt, args) = parser.parse_args()
perm = Permutate(opt.fname, opt.lname)
email_combination = fname + "." + lname + email_provider
while combination in email_combination:
print combination
if __name__ == '__main__':
compute_first_last() #this method call needs to be provided parameters