Hi how do I import files inside a txt file?

[Spencer Du]

On Monday, 2 September 2019 15:29:07 UTC+2, Joel Goldstick  wrote:
> On Mon, Sep 2, 2019 at 9:21 AM Spencer Du <spencerdu at hotmail.co.uk> wrote:
> >
> > On Monday, 2 September 2019 15:03:52 UTC+2, Joel Goldstick  wrote:
> > > On Mon, Sep 2, 2019 at 8:46 AM Spencer Du <spencerdu at hotmail.co.uk> wrote:
> > > >
> > > > On Monday, 2 September 2019 13:36:06 UTC+2, Pankaj Jangid  wrote:
> > > > > Spencer Du <spencerdu at hotmail.co.uk> writes:
> > > > >
> > > > > > How do i import files inside a txt file if they exist in the current directory?
> > > > > >
> > > > > > Here is the current code but I dont know how to do it correctly.
> > > > > >
> > > > > > import paho.mqtt.client as mqtt
> > > > > > from mqtt import *
> > > > > > import importlib
> > > > > > import os
> > > > > > import os.path
> > > > > > # from stateMachine import *
> > > > > >
> > > > > > with open("list_of_devices.txt", "r") as reader:
> > > > > >     for item in reader:
> > > > > >             try:
> > > > > >                     os.getcwd()
> > > > > >                     print("hi")
> > > > > >             except:
> > > > > >                     print("error")
> > > > > >
> > > > > > This is "list_of_devices.txt":
> > > > > > test1,test2
> > > > > >
> > > > > > Each name refers to a python file.
> > > > > >
> > > > > My interpretation is that you want to read a file (list_of_devices.txt)
> > > > > and this file contains names of other files and you want to read those
> > > > > files as well and do something with them (read or print or whatever).
> > > > >
> > > > > You can approach it like this: write a function to read a file and work
> > > > > on it. Like this,
> > > > >
> > > > > def fn(fname):
> > > > >     with open(fname, "r") as f:
> > > > >          try:
> > > > >                 # work with f
> > > > >          except:
> > > > >                 print("error")
> > > > >
> > > > > Then use this function in your code that you have writen. Like this
> > > > >
> > > > > with open("list_of_devices.txt", "r") as reader:
> > > > >      for item in reader:
> > > > >          try:
> > > > >                 fn(item)
> > > > >          except:
> > > > >                 print("error")
> > > > >
> > > > > In the example that you gave, you have written contents of
> > > > > "list_of_devices.txt" as
> > > > >
> > > > > test1,test2
> > > > >
> > > > > Take care to read them as comma separated. Or if you have control then
> > > > > write them on separate lines.
> > > > >
> > > > > Regards.
> > > > > --
> > > > > Pankaj Jangid
> > > >
> > > > Hi Pankaj
> > > >
> > > > I dont understand so what is complete code then?
> > > >
> > > > Thanks
> > > > Spencer
> > > > --
> > > > https://mail.python.org/mailman/listinfo/python-list
> > >
> > > Pardon me for guessing, but your question seems to imply that you know
> > > how you want to do something .. but I'm not sure you have tackled your
> > > problem correctly.
> > >
> > > My guess is:  Depending upon the names listed in a text file, you want
> > > to do different imports into your program.   You don't yet know how to
> > > read a file with python.
> > >
> > > First, when you run your program, python compiles it in order.  Since
> > > you don't know what you want to import until after you run your
> > > program, you can't import those modules.  You may be able to run a
> > > program to read the module list, then have it output to a new file the
> > > code you eventually want to run based on the modules you discovered.
> > > That sounds cute in a way, but probably not in a good way.  You could
> > > also surround import statements with try/except code that will import
> > > what it can, and alert you when it can't
> > >
> > > Can you give us the bigger picture of what you want to accomplish?
> > > This might lead to a better solution than the one you are thinking of
> > > now
> > >
> > > --
> > > Joel Goldstick
> > > http://joelgoldstick.com/blog
> > > http://cc-baseballstats.info/stats/birthdays
> >
> > Hi
> >
> > I have a txt file which contains the names of files. They are .py files. I want to import them into a python file if they exists in current directory and if the name of file does not exist then print out error and not import. How do I do this?
> >
> > Thanks
> > Spencer
> 
> Here is a discussion on Stack overflow that lays out how you can
> dynamically import files.  This should get you started in the right
> direction.  First, see if you can write code to read the file, and
> retrieve the names of the modules you want to import.   Come back if
> you stumble with your code for that
> 
> https://stackoverflow.com/questions/301134/how-to-import-a-module-given-its-name-as-string
> > --
> > https://mail.python.org/mailman/listinfo/python-list
> 
> 
> 
> -- 
> Joel Goldstick
> http://joelgoldstick.com/blog
> http://cc-baseballstats.info/stats/birthdays

Ok I have this code to retrieve the names of modules I want to import. Now how do I check if they exist in current directory and if they exist import them into the python program. Thanks.

with open("list_of_devices.txt", "r") as f:
	for item in f:
		print(item)