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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 import_module(module_fqname, superclasses=None):
 """Imports the module module_fqname and returns a list of defined classes from that module. If superclasses is defined then the classes returned will be subclasses of the specified superclass or superclasses. If superclasses is plural it must be a tuple of classes."""

    module_name = module_fqname.rpartition(".")[-1]
    module = __import__(module_fqname, globals(), locals(), [module_name])
    modules = [class_ for cname, class_ in
               inspect.getmembers(module, inspect.isclass)
               if class_.__module__ == module_fqname]
    if superclasses:
        modules = [m for m in modules if issubclass(m, superclasses)]

    return modules