functions.py

# quick overview of function definitions and function calls.
import some_module

# this below is a function definition, use it to generalize code to repeatedly do something.
# dnppy is full of function definitions
def my_function(argument1, argument2, default_argument3="some_default_string")
    """
    this is a function DEFINITION , and this docstring should tell you 
    something about how it works. This docstring will be displayed if someone
    uses "help(my_function)"
    """
  
    # do some stuff
    outputs = argument1 + argument2
    return outputs
    
    
# if you were to call the function above from another script in this directory, you could use
from functions import my_function           # the name of this script is "functions.py" we import from functions
my_outputs = my_function(input1, input2)    # this is where we actually call the function using our inputs.
 
 
# if you are running a function WITHIN the dnppy script that defines it, you can do so without 
# consequence by using the "magic" namespace variable "__name__" which will only be equal to 
# "__main__" if THIS script is run. anything under this statement will NOT run if this script 
# is imported from somewhere else, so it can be a good testing area.
if __name__ == "__main__":
    
    test_outs = my_function(test_input1, test_input2)
    print(test_outs)