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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 isset(alias_name):
 """Return a boolean if the docker link is set or not and is a valid looking docker link value. Args: alias_name: The link alias name """

    warnings.warn('Will be removed in v1.0', DeprecationWarning, stacklevel=2)
    raw_value = read(alias_name, allow_none=True)
    if raw_value:
        if re.compile(r'.+://.+:\d+').match(raw_value):
            return True
        else:
            warnings.warn('"{0}_PORT={1}" does not look like a docker link.'.format(alias_name, raw_value), stacklevel=2)
            return False

    return False