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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 get_class(import_path=None):
 """ Largely based on django.core.files.storage's get_storage_class """

    from django.core.exceptions import ImproperlyConfigured
    if import_path is None:
        raise ImproperlyConfigured('No class path specified.')
    try:
        dot = import_path.rindex('.')
    except ValueError:
        raise ImproperlyConfigured("%s isn't a module." % import_path)
    module, classname = import_path[:dot], import_path[dot+1:]
    try:
        mod = import_module(module)
    except ImportError as e:
        raise ImproperlyConfigured('Error importing module %s: "%s"' % (module, e))
    try:
        return getattr(mod, classname)
    except AttributeError:
        raise ImproperlyConfigured('Module "%s" does not define a "%s" class.' % (module, classname))