Using ArcPy (Python 3), I am trying to create points along a line where the elevation changes by 1 ft. I was successfully able to convert my stream to 3D using a Water Surface Grid and the Interpolate Shape tool. When I try to print the Z coordinate I get this error:

TypeError: 'float' object is not iterable

import arcpy
import os
from arcpy import env

arcpy.env.overwriteOutput = True
arcpy.CheckOutExtension("3D")
arcpy.CheckOutExtension("Spatial")
env.workspace = r"I:\1006\GIS\Tools\BFE_Tool\BFE_Tool.gdb"

streams = 'ShadrackChannel'

print ('Interpolating shape...')
stream3D = arcpy.InterpolateShape_3d(r'I:\1006\GIS\Tools\BFE_Tool\Test_Data\wsg100x', streams, 'ShadrackChannel_3D')

print ('Interpolate shape done!')

print ('Looping through polyline....')

# Enter for loop for each feature
for row in arcpy.da.SearchCursor(stream3D, ["OID@", "SHAPE@Z"]):
    # Print the current polygon or polyline's ID
    print("Feature {}:".format(row[0]))
    partnum = 0

    # Step through each part of the feature
    for part in row[1]:
        # Print the part number
        print("Part {}:".format(partnum))

        # Step through each vertex in the feature
        for pnt in part:
            if pnt:
                # Print z coordinates of current point
                print("{}".format(pnt.Z))
            else:
                # If pnt is None, this represents an interior ring
                print("Interior Ring:")

        partnum += 1

print ('Done!')

Also how can I create a point where the elevation changes every 1 foot?