Without reading the entire chunk of code, you can't tell what type of value a variable's holding. foo could be a simple integer value. It could be a list. It could be a dictionary.

@foo is always an array. %foo is always a hash.

Pay no attention to those perl scalars containing references to objects hiding behind the curtain . . . :)

Not that Python doesn't have it's nice points (xmlrpclib for example), but it has warts of its own too (trailing commas can be syntactically significant, lambda's aren't really lambda expressions (i.e. closures)).