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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 urljoin(*fragments):
 """Concatenate multi part strings into urls."""

    # Strip possible already existent final slashes of fragments except for the last one
    parts = [fragment.rstrip('/') for fragment in fragments[:len(fragments) - 1]]
    parts.append(fragments[-1])

    return '/'.join(parts)