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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 from_flags(flags, ednsflags):
 """Return the rcode value encoded by flags and ednsflags. @param flags: the DNS flags @type flags: int @param ednsflags: the EDNS flags @type ednsflags: int @raises ValueError: rcode is < 0 or > 4095 @rtype: int """


    value = (flags & 0x000f) | ((ednsflags >> 20) & 0xff0)
    if value < 0 or value > 4095:
        raise ValueError('rcode must be >= 0 and <= 4095')
    return value