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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 _is_mostly_subdomain_compatible(bucket_name):
 This checks to make sure that putting aside certificate validation issues that a bucket_name is able to use the SubdomainCallingFormat. """

    return (bucket_name.lower() == bucket_name and
            len(bucket_name) >= 3 and
            len(bucket_name) <= 63 and
            '_' not in bucket_name and
            '..' not in bucket_name and
            '-.' not in bucket_name and
            '.-' not in bucket_name and
            not bucket_name.startswith('-') and
            not bucket_name.endswith('-') and
            not bucket_name.startswith('.') and
            not bucket_name.endswith('.') and
            not _is_ipv4_like(bucket_name))