A bit unclear what you want but you should be able to use [collections.defaultdict][1]:

> Using list as the default_factory, it is easy to group a sequence of
> key-value pairs into a dictionary of lists

    import arcpy
    from collections import defaultdict
    fc = r"C:\folder\shapefile.shp"
    dx = defaultdict(list)
    dy = defaultdict(list)
    
    with arcpy.da.SearchCursor(fc,['OID@','SHAPE@']) as cursor:
        for row in cursor:
            array1=row[1].getPart()
            for vertice in range(row[1].pointCount):
                pnt=array1.getObject(0).getObject(vertice)
                dx[row[0]].append(pnt.X)
                dy[row[0]].append(pnt.Y)

You will now have two dictionaries with ObjectID as key and a list of coordinates for each polygon as values . For example all the vertices for the first polygon (objectid 0) as lists:

    print(dx[0])
    print(dy[0])
    >>[800000.0, 800000.0, 700000.0, 700000.0, 800000.0]
    >>[7400000.0, 7300000.0, 7300000.0, 7400000.0, 7400000.0]

Start and end coordinates are the same. Can be removed if you want.

  [1]: https://docs.python.org/2/library/collections.html#defaultdict-objects