#Import all functions from arcpy
from arcpy import *

#Name of layer
#!!Change me as needed
Layer = "TestFC"

#Fields to check
#!!Change me as needed too
SCfields = ["src_RefName", "North", "South", "East", "West"]
UCfields = ["src_RefName", "n", "s", "e", "w"]

#Create empty dictionaries
Ndi = {}
Sdi = {}
Edi = {}
Wdi = {}

#create SearchCursor object
cursor = da.SearchCursor (Layer, SCfields)
#Iterate through rows
for row in cursor:
    #Dictionary logic tree
    if row[1]:
        if not row[0] in Ndi:
            Ndi[row[0]] = [row[1]]
        else:
            Ndi[row[0]].append(row[1])
    if row[2]:
        if not row[0] in Sdi:
            Sdi[row[0]] = [row[2]]
        else:
            Sdi[row[0]].append(row[2])
    if row[3]:
        if not row[0] in Edi:
            Edi[row[0]] = [row[3]]
        else:
            Edi[row[0]].append(row[3])
    if row[4]:
        if not row[0] in Wdi:
            Wdi[row[0]] = [row[4]]
        else:
            Wdi[row[0]].append(row[4])

del cursor

#create UpdateCursor
cursor = da.UpdateCursor (Layer, UCfields)
#Iterate through rows
for row in cursor:
    #Update logic tree
    if row[0] in Ndi:
        row[1] = ",".join(map(str, Ndi[row[0]]))
    if row[0] in Sdi:
        row[2] = ",".join(map(str, Sdi[row[0]]))
    if row[0] in Edi:
        row[3] = ",".join(map(str, Edi[row[0]]))
    if row[0] in Wdi:
        row[4] = ",".join(map(str, Wdi[row[0]]))
    cursor.updateRow(row)
del cursor
print "Done"

SCfields = ["src_RefName", "North", "South", "East", "West"]
UCfields = ["src_RefName", "n", "s", "e", "w"]

#Import all functions from arcpy
from arcpy import *

#Name of layer
#!!Change me as needed
Layer = "TestFC"

#Fields to check
#!!Change me as needed too
SCfields = ["src_RefName", "North"]
UCfields = ["src_RefName", "n"]

#Create empty dictionaries
Ndi = {}

#create SearchCursor object
cursor = da.SearchCursor (Layer, SCfields)
#Iterate through rows
for row in cursor:
    #Dictionary logic tree
    if row[1]:
        if not row[0] in Ndi:
            Ndi[row[0]] = [row[1]]
        else:
            Ndi[row[0]].append(row[1])
del cursor

#create UpdateCursor
cursor = da.UpdateCursor (Layer, UCfields)
#Iterate through rows
for row in cursor:
    #Update logic tree
    if row[0] in Ndi:
        row[1] = ",".join(map(str, Ndi[row[0]]))
del cursor
print "Done"