Unable to Update Map Element

I’m trying to update my text elements, but after running script no changes occur and no error are triggered. Running suggested code triggered an error.

I need to update my title and date text box.

I used the suggested script and receive:

Runtime error 
Traceback (most recent call last):
File "<string>", line 72, in <module>
ImportError: No module named mapping

Here’s what I have so far:

# Import arcpy module
import arcpy

#Work Env
arcpy.env.workspace = "F:APPDATAGISMAPSProjectsPlanningRequestsBryan2018PlanningTeresita_careTest_File"

# Script arguments
Parcels = arcpy.GetParameterAsText(0)

Selection_type = arcpy.GetParameterAsText(1)
if Selection_type == '#' or not Selection_type:
    Selection_type = "NEW_SELECTION" # provide a default value if unspecified

Distance__value_or_field_ = arcpy.GetParameterAsText(2)
if Distance__value_or_field_ == '#' or not Distance__value_or_field_:
    Distance__value_or_field_ = "300 Feet" # provide a default value if unspecified

Distance__value_or_field___2_ = arcpy.GetParameterAsText(3)
if Distance__value_or_field___2_ == '#' or not Distance__value_or_field___2_:
    Distance__value_or_field___2_ = "500 Feet" # provide a default value if unspecified

Expression = arcpy.GetParameterAsText(4)
if Expression == '#' or not Expression:
    Expression = ""AIN" = '7050005016'" # provide a default value if unspecified

v300ft_shp = arcpy.GetParameterAsText(5)

v500ft_shp = arcpy.GetParameterAsText(6)

# Local variables:
#Parcel_Address = Parcels

#If layer already exist overwrite
arcpy.env.overwriteOutput=True

#Create Parcels layer
arcpy.MakeFeatureLayer_management("F:/APPDATA/GISMAPS/Projects/Planning/Requests/Bryan/2018/Planning/Teresita_care/Test_File/Parcels.shp","Parcels.lyr")


# Process: Select Layer By Attribute
arcpy.SelectLayerByAttribute_management("Parcels.lyr", Selection_type, Expression)

# identify the current map document

mxd = arcpy.mapping.MapDocument('CURRENT')

# identify the data frame
df = arcpy.mapping.ListDataFrames(mxd)[0]

# use the zoom to selected features method of the data frame to update the extent
df.zoomToSelectedFeatures ()

#Set Scale
df.scale = 3860

# Process: Buffer
arcpy.Buffer_analysis("Parcels.lyr", "F:/APPDATA/GISMAPS/Projects/Planning/Requests/Bryan/2018/Planning/Teresita_care/Test_File/samv300ft_shp", Distance__value_or_field_, "FULL", "ROUND", "NONE", "", "PLANAR")

#Import Symbology layer to buffer
arcpy.ApplySymbologyFromLayer_management ("samv300ft_shp", "F:/APPDATA/GISMAPS/Projects/Planning/Requests/Bryan/2018/Planning/Teresita_care/Test_File/Symbol_300ft.lyr")

# Process: Buffer (2)
arcpy.Buffer_analysis("Parcels.lyr", "F:/APPDATA/GISMAPS/Projects/Planning/Requests/Bryan/2018/Planning/Teresita_care/Test_File/samv500ft_shp", Distance__value_or_field___2_, "FULL", "ROUND", "NONE", "", "PLANAR")

#Import Symbology layer to buffer
arcpy.ApplySymbologyFromLayer_management ("samv500ft_shp", "F:/APPDATA/GISMAPS/Projects/Planning/Requests/Bryan/2018/Planning/Teresita_care/Test_File/Symbol_300ft.lyr")


import arcpy
import os
import sys
import mapping as m

# Folder containing MXD's 
folder = r'F:APPDATAGISMAPSProjectsPlanningRequestsBryan2018PlanningTeresita_careTest_FileTest_Script.mxd' 
arcpy.env.workspace = folder   

# Find and Replace text element 
find_elm = 'TEXT_ELEMENT' 
replace_elm = 'Text you want to replace find_elm'  
# Find all .mxd files in folder 
# replaces text element in mxd if it exists
for mapDoc in arcpy.ListFiles('*.mxd'):
    mxd = arcpy.mapping.MapDocument(os.path.join(folder, mapDoc))
    for elm in arcpy.mapping.ListLayoutElements(mxd, 'TEXT_ELEMENT'):
        if elm.text == find_elm:
            elm.text = replace_elm
            print 'Replaced {0} in {1}'.format(find_elm, mapDoc)
    mxd.save()
    del mxd  

import arcpy, os from arcpy 
import mapping as m  
# Folder containing MXD's 
folder = r'C:pathto_yourmapdocuments' 
arcpy.env.workspace = folder   

# Find and Replace text element 
find_elm = 'Text you want to find' 
replace_elm = 'Text you want to replace find_elm'  
# Find all .mxd files in folder 
# replaces text element in mxd if it exists
for mapDoc in arcpy.ListFiles('*.mxd'):
    mxd = arcpy.mapping.MapDocument(os.path.join(folder, mapDoc))
    for elm in arcpy.mapping.ListLayoutElements(mxd, 'TEXT_ELEMENT'):
        if elm.text == find_elm:
            elm.text = replace_elm
            print 'Replaced {0} in {1}'.format(find_elm, mapDoc)
    mxd.save()
    del mxd