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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 get_share_file (filename, devel_dir=None):
 """Return a filename in the share directory. @param devel_dir: directory to search when developing @ptype devel_dir: string @param filename: filename to search for @ptype filename: string @return: the found filename or None @rtype: string @raises: ValueError if not found """

    paths = [get_share_dir()]
    if devel_dir is not None:
        # when developing
        paths.insert(0, devel_dir)
    for path in paths:
        fullpath = os.path.join(path, filename)
        if os.path.isfile(fullpath):
            return fullpath
    # not found
    msg = "%s not found in %s; check your installation" % (filename, paths)
    raise ValueError(msg)