Would someone walk through this python function with me to better understand it dealing with dict

Question

Could someone walk through this with me, maybe adding #s notes between each line?
many thanks. I've been doing really well, but had to move on from this exercise and I just want to make sure I fully understand it
Write a function named members that takes two arguments, a dictionary and a list of keys. Return a count of how many of the items in the list are also keys in the dictionary.
The function i found to work was 
Python
def members(my_dict, my_list):
  total = 0
  for x in my_list:
      if x in my_dict:
         total += 1
  return total

Now I kinda get the function operation, but how could I get this fuction to run in an actual program
would I also create var for mydict and mylist inside the function or would I create like a input var to add to mydict and mylist
how would I actually get it to show my result? print members or print total? 
Maybe I should go back to the shopping list python function exercise and try to hybrid this dict exercise into it?
Sorry for the rambling, my brain is numb right now

Ben Fishbein · Answer

def members(mydict, mylist):
  total = 0
  for x in mylist:
      if x in mydict:
         total += 1
  return total
Now I kinda get the function operation, but how could I get this fuction to run in an actual program
Call the function. For example, in the main part of the program:
create variables for dictionary and list
eldicto = {1: "monkey", "tower": "skunk", "pants": 5}
ellisto = ["pants", "shirt", "socks"]
now call the function
members(eldicto, ellisto)
would I also create var for mydict and mylist inside the function or would I create like a input var to add to mydict and mylist
No. You don't need to create the variable within the function. Putting it in the parentheses when you call the function will make it a variable inside the function.
how would I actually get it to show my result? print members or print total?
If you want to print from within the function, you can do it like this:
def members(mydict, mylist):
  total = 0
  for x in mylist:
      if x in mydict:
         total += 1
  print total
  return total
If you want to print it outside the function...like this:
print members(eldicto, ellisto)
Or assign the results of the function to a variable and then print it:
results = members(eldicto, ellisto)
print results
You can't print "total" outside of the function, because it doesn't exist anymore...it only exists within the function "members."

Martin Cornejo Saavedra · Answer

"how would I actually get it to show my result? print members or print total?"
You can do this to show output:
python
a_dict = {'animal':'dog', 'name':'spark'}
a_list = ['animal', 'age']
matches = members(a_dict, a_list)
print("There are {} keywords in your list.".format(matches))

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brian albano

brian albano

Would someone walk through this python function with me to better understand it dealing with dict

2 Answers

Martin Cornejo Saavedra

Martin Cornejo Saavedra

brian albano

brian albano

Ben Fishbein

Ben Fishbein

create variables for dictionary and list

now call the function

brian albano

brian albano