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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 allow_access_to_instance(self, _, ip_address):
        ''' Allow access to instance. '''
        if not self.connect_to_aws_rds():
            return False
        try:
            conn = boto.ec2.connect_to_region(
                self.region,
                aws_access_key_id=self.aws_access_key_id,
                aws_secret_access_key=self.aws_secret_access_key
            )
            sgs = conn.get_all_security_groups('default')
            default_sg = sgs[0]
            default_sg.authorize(ip_protocol='tcp', from_port=3306,
                                 to_port=3306, cidr_ip=str(ip_address)+'/32')
        except EC2ResponseError, exception:
            if exception.error_code == "InvalidPermission.Duplicate":
                return True  # ok it already exists
            else:
                return False
        else:
            return True