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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_schema(brain_or_object):
 """Get the schema of the content :param brain_or_object: A single catalog brain or content object :type brain_or_object: ATContentType/DexterityContentType/CatalogBrain :returns: Schema object """

    obj = get_object(brain_or_object)
    if is_portal(obj):
        fail("get_schema can't return schema of portal root")
    if is_dexterity_content(obj):
        pt = get_tool("portal_types")
        fti = pt.getTypeInfo(obj.portal_type)
        return fti.lookupSchema()
    if is_at_content(obj):
        return obj.Schema()
    fail("{} has no Schema.".format(brain_or_object))