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Solve the following problem using Python, implementing the functions described below, one line at a time
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Description:
 def assoc(objects, sitecol, assoc_dist, mode, asset_refs=()):
 """ Associate geographic objects to a site collection. :param objects: something with .lons, .lats or ['lon'] ['lat'], or a list of lists of objects with a .location attribute (i.e. assets_by_site) :param assoc_dist: the maximum distance for association :param mode: if 'strict' fail if at least one site is not associated if 'error' fail if all sites are not associated :returns: (filtered site collection, filtered objects) """

    if isinstance(objects, numpy.ndarray) or hasattr(objects, 'lons'):
        # objects is a geo array with lon, lat fields or a mesh-like instance
        return _GeographicObjects(objects).assoc(sitecol, assoc_dist, mode)
    else:  # objects is the list assets_by_site
        return _GeographicObjects(sitecol).assoc2(
            objects, assoc_dist, mode, asset_refs)