I have a visit tool (in C#, converted from VB.net, which was upgraded from VB6 which was influenced by a tool I wrote in AML)... anyway, the key is to use the Envelope of the geometry in the case of polygon, polyline or multipoint and recentre the map extent.
Here is a very basic start for you:
mxd = arcpy.mapping.MapDocument('CURRENT')
df = arcpy.mapping.ListDataFrames(mxd, "Layers") 
Envelopes =  # store extents here
# find the selection set
SelLayer = arcpy.mapping.ListLayers(mxd,data_frame=df) # first layer
fidSet = arcpy.Describe(SelLayer).FIDSet
if len(fidSet) == 0:
# now cursor through it an get the geometries
# storing their extents into a list
with arcpy.da.SearchCursor(SelLayer,"SHAPE@") as SCur:
for feat in SCur:
# I'm going to assume polygon/polyline
Envelopes.append(feat.extent) # grab the envelope
df.extent = Envelopes # first extent
First you need to check there is a selction against the layer, if there is cursor through the records (remember that if there is a selection against a layer only the selected records are returned) using SHAPE@ to get the geometry object which has an extent as a property, store these in a list and then calling the first one to set the current dataframe extent (also a property).
Note that once the list is made the selection can be changed, this may or may not be what you want. In my case I wanted the extents to remain and be able to edit as I went through the list.