How to use the eel.init function in Eel

from __future__ import print_function	# For Py2/3 compatibility
import eel
import random

eel.init('web')

@eel.expose
def py_random():
    return random.random()

def print_num(n):
    print('Got this from Javascript:', n)

# Call Javascript function, and pass explicit callback function    
eel.js_random()(print_num)

# Do the same with an inline callback
eel.js_random()(lambda n: print('Got this from Javascript:', n))

eel.start('callbacks.html', size=(400, 300))

from __future__ import print_function	# For Py2/3 compatibility
import eel, random

eel.init('web')

@eel.expose
def py_random():
    return random.random()

eel.start('sync_callbacks.html', block=False, size=(400, 300))

# Synchronous calls must happen after start() is called

# Get result returned synchronously by 
# passing nothing in second brackets
#                   v
n = eel.js_random()()
print('Got this from Javascript:', n)

while True:

import eel

eel.init('web/')                     # Give folder containing web files

@eel.expose                         # Expose this function to Javascript
def say_hello_py(x):
    print('Hello from %s' % x)

say_hello_py('Python World!')
eel.say_hello_js('Python World!')   # Call a Javascript function

eel.start('templates/hello.html', size=(300, 200), templates='templates')    # Start

import eel

# Set web files folder and optionally specify which file types to check for eel.expose()
eel.init('web')

# disable_cache now defaults to True so this isn't strictly necessary. Set it to False to enable caching.
eel.start('disable_cache.html', size=(300, 200), disable_cache=True)    # Start

from __future__ import print_function	# For Py2/3 compatibility
import eel

eel.init('web')                     # Give folder containing web files

@eel.expose                         # Expose this function to Javascript
def handleinput(x):
    print('%s' % x)

eel.say_hello_js('connected!')   # Call a Javascript function

eel.start('main.html', size=(500, 200))    # Start

def start_eel(develop):
    """Start Eel with either production or development configuration"""
    if develop:
        directory = 'src'
        app = None
        page = {'port': 3000}
        flags = ['--auto-open-devtools-for-tabs']
    else:
        directory = 'build'
        app = 'chrome-app'
        page = 'index.html'
        flags = []

    eel.init(directory, ['.tsx', '.ts', '.jsx', '.js', '.html'])

    # These will be queued until the first connection is made, but won't be repeated on a page reload
    say_hello_py('Python World!')
    eel.say_hello_js('Python World!')   # Call a JavaScript function (must be after `eel.init()`)

    eel.start(page, size=(1280, 800), options={
        'mode': app,
        'port': 8080,
        'host': 'localhost',
        'chromeFlags': flags
    })

import os
import platform
import sys

# Use latest version of Eel from parent directory
sys.path.insert(1, '../../')
import eel

# Use the same static files as the original Example
os.chdir(os.path.join('..', '01 - hello_world'))

# Set web files folder and optionally specify which file types to check for eel.expose()
eel.init('web', allowed_extensions=['.js', '.html'])


@eel.expose                         # Expose this function to Javascript
def say_hello_py(x):
    print('Hello from %s' % x)


say_hello_py('Python World!')
eel.say_hello_js('Python World!')   # Call a Javascript function

# Launch example in Microsoft Edge only on Windows 10 and above
if sys.platform in ['win32', 'win64'] and int(platform.release()) >= 10:
    eel.start('hello.html', mode='edge')
else:
    raise EnvironmentError('Error: System is not Windows 10 or above')

def setup():
     eel.init('web')