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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 escape_header(val):
 """Escapes a value so that it can be used in a mime header"""


    if val is None:
        return None
    try:
        return quote(val, encoding="ascii", safe="/ ")
    except ValueError:
        return "utf-8''" + quote(val, encoding="utf-8", safe="/ ")