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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 exists_in_registry(category, namespace, name):
 """ See if a given category, namespace, name combination exists in the registry category - See registrycategories. Type of module namespace - Namespace of the module, defined in settings name - the lowercase name of the module """

    selected_registry = [re for re in registry if re.category==category and re.namespace==namespace and re.name == name]
    if len(selected_registry)>0:
        return True
    return False