human
I am working on the file "Python_Misc/TMWP_DFBuilder_OO_PY/testing_and_documentation/TMWP_DFBuilder_AbstractClass_Module_Testing.ipynb".
The first task is:
Test Sub Class
Before creating, testing, and debugging a subclass that uses a Google maps API to enrich the data, it is desirable to start simpler.  This test object makes use of all of the same logic except for the API calls out to the web to get new data.  For this test, the "delay" will be set to 0 since it is not needed.  This code just shows that we can loop through an original DF, copy rows 5 at a time to a temporary DF, add columns to them using logic that looks at existing rows, and output to our output DF.
Stopping the code in the middle may allow us to test what happens if the code halts, showing what is stored in the dataframe in the object when this happens.
Can you write Python program for it?
assistant
#Here happens if the code halts, showing what is stored in the dataframe in the object when this happens.

class TstModification_DFBuilder(DFBuilder): 
    '''Test of ability to scan a dataframe x rows at a time and add data columns to it.
There are more efficient ways to round cols in a DF; this object is a test of base logic from the abstract class
ahead of creating a more complex subclass that interacts with the web during the loop.  It builds a copy of the 
DF a small number of rows at a time and creates some new fields as it does so.  Input DF must have "lat" and 
"lon" cols. lat=Latitude / lon = Longitude. Defaults set delay to 0 seconds and rows processed at a time to 
5 for this test.'''
    
    def __init__(self, endRw=5,time_delay=0):           
        super().__init__(endRw,time_delay)
        
    def roundValue(self, value, dec_places=4, rtn_null=False):
        '''Takes arguments: value, dec_places. Rounds value to dec_places specified (if not specified, default=4.)
rtn_null defaults to False.  If True, error handling should result in an empty string being returned.   
If false __ErrType__ should be returned to help with debugging code and data by distinguishing why there is  
no rounded answer returned.  Testing shows that while using round() throws errors if input is not a number, 
applying it to a dataframe does not.  Try-except code left in for future research but does not seem to ever 
get triggered as of this writing.'''
        
        try:
            rtnVal = round(value, dec_places)
        except TypeError as terr:
            print(type(terr))
            print(terr)
            rtnVal = "__NAN__"
        except Exception as eerr:
            print(type(eerr))
            print(eerr)
            rtnVal = "__ERR__"
        finally:
            if rtn_null==True:
                if isinstance(rtnVal, str):
                    return ""
                elif rtnVal is None:
                    return ""
                else:
                    return rtnVal
            else: 
                return rtnVal
        
    def _modifyTempDF_(self, dec_places=4, rtn_null=False):
       ...