Making multiple fields NULL using Python in ArcGIS?

Question

I have a repetitive task here at work. It requires that I make multiple fields NULL as I update the geodatabase. Is there a script I can write that I can input the fields and the feature class. Then make all those fields NULL. This script must not make everything NULL in the feature class, only the fields designated. import arcpy

fc = "N:\Updates\CarsonCityNV\CarsonCityNV.gdb\J_POC_S_Studies_Ln"

with arcpy.da.UpdateCursor(fc, ("C1_GAGE", "C2_DISCH", "C3_MODEL", "C4_FCSTR", "C5_CHANN", "C6_HSTR, "C7_SCOUR", "S1_REGEQ", "S2_REPLO",     "S3_IMPAR", "S4_HSTR", "S5_CHIMP", "S6_TOPO", "S7_VEGLU", "S9_HWMS", "S10_REGEQ", "CE_TOTAL", "SE_TOTAL", "A1_TOPO", "A2_HYDRO", "A3_IMPAR", "A4_TECH", "A5_FOAPASS")) as cursor:
 for row in cursor:
    row[0] = None
    row[1] = None
    row[2] = None
    row[3] = None
    row[4] = None
    row[5] = None
    row[6] = None
    row[7] = None
    row[8] = None
    row[9] = None
    row[10] = None
    row[11] = None
    row[12] = None
    row[13] = None
    row[14] = None
    row[15] = None
    row[16] = None
    row[17] = None
    row[18] = None
    row[19] = None
    row[20] = None
    row[21] = None
    row[22] = None
    cursor.updateRow(row)

I'm getting a parsing error on line 5.

Answer 1

Just change the path of fc to your feature class, and change YourField to the field name.

import arcpy

fc = "C:\\Temp\\Data.gdb\\FeatureClass"

with arcpy.da.UpdateCursor(fc, ("YourField")) as cursor:
    for row in cursor:
        row[0] = None
        cursor.updateRow(row)

To do multiple fields, just add another field to the tuple and set the row equal to None:

import arcpy

fc = "C:\\Temp\\Data.gdb\\FeatureClass"

with arcpy.da.UpdateCursor(fc, ("YourField", "YourField2")) as cursor:
    for row in cursor:
        row[0] = None
        row[1] = None
        cursor.updateRow(row)