Python module functions not available in shiny app

reticulate

#1

I am trying to create a shiny app which will plot and, ultimately, perform graphical 'arithmetic' for real elliptic curves. I have created some useful R plotting scripts contained in 'ECPlotting.r' which rely on a python module I created a few years ago, 'allzerosB.py'. The two work fine together when loaded from the command line in R after calling library(reticulate). However, when I try essentially the same thing from within the app, the UI is created fine but none of the functions in the python module are created. All relevant .r files and the python file 'allzerosB.py' are in the appropriate app folder. Here is the app header:

library(shiny)
library(shinyjs)
library(reticulate)
source('ECPlotting.r')
source_python('allzerosB.py')

The error message which appears in the UI is simply:

Error: Could not find function 'allzeros'

'allzeros' is a function contained the module 'allzerosB.py'. In fact, when I list objects available in the consolr after running the app, none of the functions in 'allzerosB.py' have been created.
It seems strange that 'reticulate' would enable me to use the python module in an ordinary R session but not when used from within a shiny app. Any suggestions would be appreciated.