Using ArcPy with map documents  

Esri designed the arcpy module to not only work with data but also included the arcpy.mapping module for direct interaction with MXDs and the layers they contain. This module opens up a multitude of map automation possibilities. A script might aid in identifying broken layer links, update the data source of these layers, and apply new color schemes to layers. Another script might use a map template to create a set of maps, one from each feature class in a feature dataset. A third script could create a map book from an MXD, moving from cell to cell in a grid layer to output the pages of the book, or even calculating the coordinates on the fly. Dynamically created maps, based on data from a fresh analysis, can be created as data is produced. The arcpy.mapping module moves the arcpy module from helpful to instrumental in any geospatial work flow...