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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 CheckProg(context, prog_name):
 """Simple check if a program exists in the path. Returns the path for the application, or None if not found. """

    res = SCons.Conftest.CheckProg(context, prog_name)
    context.did_show_result = 1
    return res