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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 has_reg(value):
 """Return True if the given key exists in HKEY_LOCAL_MACHINE, False otherwise."""

    try:
        SCons.Util.RegOpenKeyEx(SCons.Util.HKEY_LOCAL_MACHINE, value)
        ret = True
    except SCons.Util.WinError:
        ret = False
    return ret