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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 issue_line(issue):
 """Returns log line for given issue."""

    template = '#{number} {tags}{title}'
    tags = issue_tags(issue)
    params = {
        'title': issue['title'].capitalize().rstrip('.'),
        'number': issue['number'],
        'tags': ' '.join('[{}]'.format(tag) for tag in tags) + (' ' if tags else '')
    }
    return template.format(**params)