I need help on this error message

Question

I need help on this error message
I was trying to write a custom python script for Definition query for a particular layer and this error message was what i got 
NameError: name 'field' is not defined

after entering the following codes - 
#Variables to form defintion query
field = '"Name_Allottee"'
value = "'Fadare A Adetoye'"
#concatenate query syntax
queryStr = "Name_Allottee" + "=" + "Fadare A Adetoye"
#Specify the MXD project (CURRENT), dataframe (Layers)
mxd = arcpy.mapping.MapDocument("CURRENT")
df = arcpy.mapping.ListDataFrames(mxd, "Layers")
#Apply defintion query to specified layer group (KWAGIS_Parcels)
for lyr in arcpy.mapping.ListLayers(mxd, "KWAGIS_Parcel", df):
if lyr.supports("DEFINITIONQUERY"):
lyr.definitionQuery = queryStr
arcpy.RefreshActiveView()

BruceNielsen · Answer

A SelectLayerByAttribute statement without the query statement is like saying "SELECT ALL FROM...". Since you're accepting a SQL statement as a parameter, I believe you want something like this:arcpy.SelectLayerByAttribute_management(FeatureClass, "NEW_SELECTION", SQLStatement)

OLANIYANOLAKUNLE · Answer

i used the following python script to create a script tool to select an attribute of a particular feature, but it returns all the records of the feature specified in the FeatureClass;

import arcpy
arcpy.env.overwriteOutput = True

try:
    # Get the input parameters for the selection tool
    FeatureClass = arcpy.GetParameterAsText(0)
    SQLStatement = arcpy.GetParameterAsText(1)
    
    # Select by Layer Attribute
    arcpy.SelectLayerByAttribute_management(FeatureClass, "NEW_SELECTION", "")

# Report a success message    
    arcpy.AddMessage("All done!")

except:
    # Report an error messages
    arcpy.AddError("Could not complete the selection")

# Report any error messages that the selection tool might have generated    
    arcpy.AddMessage(arcpy.GetMessages())

Please any suggestions. Thanks

OLANIYANOLAKUNLE · Answer

mxd = arcpy.mapping.MapDocument("Current")
        df = arcpy.mapping.ListDataFrames(mxd)[0]
        lyr= arcpy.mapping.ListLayers(mxd,"Parcels")[0]
        lyr.definitionQuery = '"Name_Allottee" =\'Fadara A Adatoyo\''
        arcpy.RefreshTOC()
        arcpy.RefreshActiveView()