lazily importing flask

[kzidane]

When flask is imported before cs50:

$ cat application.py
from flask import Flask, jsonify
from cs50 import SQL

app = Flask(__name__)
db = SQL('sqlite:///test.db')

@app.route('/')
def index():
    return jsonify(db.execute('select 1'))
$ flask run
 * Serving Flask app "application.py" (lazy loading)
 * Environment: development
 * Debug mode: off
 * Running on http://localhost:8080/ (Press CTRL+C to quit)
 * Restarting with stat
DEBUG:cs50:select 1
INFO:werkzeug:172.17.0.1 - - [31/Oct/2019 14:30:08] "GET / HTTP/1.1" 200 -

$ curl http://localhost:8080
[{"1":1}]

When flask is imported after cs50:

$ cat application.py
from cs50 import SQL
from flask import Flask, jsonify

app = Flask(__name__)
db = SQL('sqlite:///test.db')

@app.route('/')
def index():
    return jsonify(db.execute('select 1'))
$ flask run
 * Serving Flask app "application.py" (lazy loading)
 * Environment: development
 * Debug mode: off
 * Running on http://localhost:8080/ (Press CTRL+C to quit)
 * Restarting with stat
DEBUG:cs50:select 1
INFO:werkzeug:172.17.0.1 - - [31/Oct/2019 14:32:19] "GET / HTTP/1.1" 200 -

$ curl http://localhost:8080
[{"1":1}]

Importing get_*:

$ time python3 -c 'from cs50 import get_string'

real    0m0.076s
user    0m0.068s
sys     0m0.008s

[kzidane]

And just for completeness, logger is disabled when using the interpreter (and by default):

$ python3
Python 3.7.3 (default, Oct 28 2019, 16:05:54)
[GCC 7.4.0] on linux
Type "help", "copyright", "credits" or "license" for more information.
>>> from cs50 import SQL
>>> db = SQL('sqlite:///test.db')
>>> db.execute('select 1')
[{'1': 1}]