obj = 'Plane'
import bpy
bpy.context.scene.objects.active = bpy.data.objects[obj]
bpy.ops.object.mode_set(mode='EDIT')
bpy.data.objects[obj].select=False
(x, y, z) = bpy.data.objects[obj].data.vertices[733].co
dx = x - -0.73204699604
dy = y - 0.500198245049
dz = 0
bpy.ops.object.mode_set(mode='OBJECT')
bpy.data.objects[obj].data.vertices[733].select = True
bpy.ops.object.mode_set(mode='EDIT')
bpy.ops.transform.translate(value=(dx , dy, dz), proportional='ENABLED', proportional_size=0.1, proportional_edit_falloff='SMOOTH')
bpy.ops.object.mode_set(mode='OBJECT')
bpy.data.objects[obj].data.vertices[733].select = False