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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 validate(self, meta, val):
 """Validate an account_id"""

        val = string_or_int_as_string_spec().normalise(meta, val)
        if not regexes['amazon_account_id'].match(val):
            raise BadOption("Account id must match a particular regex", got=val, should_match=regexes['amazon_account_id'].pattern)
        return val