How can I import a dictionary created by one script into another script?

Question

I have one python file named testings.py, in this file I derive a dictionary by using web scraping of relevant data. To populate the dictionary takes a few minutes.

What I would like to do, instead of copying the whole script into my other python script named webscraper.py, and then running the whole of both scripts in effect every time I run webscraper.py, is instead import the dictionary from the testing.py script into the second script webscraper.py and then save myself those minutes everytime I run webscraper.py.

Every so often my dictionary will be out of date, in which case I would just run testings.py before starting webcraper.py. Is there a way to do what I'm asking?

Another thing to note is that, at the start of testings.py I have my_dict = {} and it's not until the end of the script that my_dict is fully populated. So when I import it I want to import the fully populated version of it as if the script had run fully.

I'm starting to think that this isn't possible, as the testings.py script would need to run to get the my_dict dictionary populated. And my_dict wouldn't be saved anywhere on my pc to import it into webscraper.py. Unless I added some code in testings.py to save the dictionary to a csv file and then in webscraper.py I got it to read the CSV file. Maybe this would be a solution? — pvmlad, Feb 05 '20 at 00:55
you can pickle the dictionary at whichever state you want and then read the pickle back in later. The pickle knows the object is a dictionary and has all the keys/values in the dictionary as of the time of the pickle dump. Would that achieve what you want? — Lucas Roberts, Feb 05 '20 at 00:56
Yes, there's a way to do what you want. See [Saving an Object (Data persistence)](https://stackoverflow.com/questions/4529815/saving-an-object-data-persistence). — martineau, Feb 05 '20 at 00:57

score 1 · Answer 1 · answered Feb 05 '20 at 01:00

You can either save the dictionary in a number of ways to file (check out https://docs.python.org/3/library/pickle.html or https://docs.python.org/3/library/json.html and how to write files, https://docs.python.org/3/library/io.html?highlight=open) and then read it from the other script.

Or you can just import the scraping script into the other script and call the scraping function from there, returning the result - but that's only a solution if you don't mind running the scraping there and then and you're not looking to reuse the results of an earlier scrape.

score 0 · Answer 2 · answered Feb 05 '20 at 01:21

When I run this script :

from tester import my_dict
print ('Now in second script.')
print (my_dict)

It actually runs the script called tester.py and then imports and prints my_dict.

my_dict = {}
for x in range (20) :
    for y in range (10) :
        my_dict [x] = y
print (my_dict)
input ('All done now.')

How can I import a dictionary created by one script into another script?

2 Answers2