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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 set_fd_value(tag, value):
 """ Setters for data that also work with implicit transfersyntax :param value: the value to set on the tag :param tag: the tag to read """

    if tag.VR == 'OB' or tag.VR == 'UN':
        value = struct.pack('d', value)
    tag.value = value