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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 format_cert_name(env='', account='', region='', certificate=None):
 """Format the SSL certificate name into ARN for ELB. Args: env (str):
 Account environment name account (str):
 Account number for ARN region (str):
 AWS Region. certificate (str):
 Name of SSL certificate Returns: str: Fully qualified ARN for SSL certificate None: Certificate is not desired """

    cert_name = None

    if certificate:
        if certificate.startswith('arn'):
            LOG.info("Full ARN provided...skipping lookup.")
            cert_name = certificate
        else:
            generated_cert_name = generate_custom_cert_name(env, region, account, certificate)
            if generated_cert_name:
                LOG.info("Found generated certificate %s from template", generated_cert_name)
                cert_name = generated_cert_name
            else:
                LOG.info("Using default certificate name logic")
                cert_name = ('arn:aws:iam::{account}:server-certificate/{name}'.format(
                    account=account, name=certificate))
    LOG.debug('Certificate name: %s', cert_name)

    return cert_name