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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 vlink(s_expnum, s_ccd, s_version, s_ext, l_expnum, l_ccd, l_version, l_ext, s_prefix=None, l_prefix=None):
 """make a link between two version of a file. @param s_expnum: @param s_ccd: @param s_version: @param s_ext: @param l_expnum: @param l_ccd: @param l_version: @param l_ext: @param s_prefix: @param l_prefix: @return: """

    source_uri = get_uri(s_expnum, ccd=s_ccd, version=s_version, ext=s_ext, prefix=s_prefix)
    link_uri = get_uri(l_expnum, ccd=l_ccd, version=l_version, ext=l_ext, prefix=l_prefix)

    return client.link(source_uri, link_uri)