Don't know how to get rid of that message?
input_shp = fc
arr = arcpy.Array()
with arcpy.da.UpdateCursor(input_shp,['FID','SHAPE@']) as cur:
extents = []
for row in cur:
ext = row[1].extent
p0 = ext.lowerLeft; p1 = ext.upperRight
print('Extent of shape... {}: '.format(row[0]))
print(' X min/max {}, {}'.format(ext.XMin,ext.XMax))
Xmin = round((ext.XMin), 0)
print (Xmin)
row.setValue(fld_xmin, Xmin)
print ( ' X min, {}'.format(ext.XMin))
curs.updateRow(row)
print(' Y min/max {}, {}'.format(ext.YMin,ext.YMax))
arr.add(p0)
arr.add(p1)
mp = arcpy.Multipoint(arr)
print('Extent of all {}'.format(mp.extent))
