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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 _defines(prefix, defs, suffix, env, c=_concat_ixes):
 """A wrapper around _concat_ixes that turns a list or string into a list of C preprocessor command-line definitions. """


    return c(prefix, env.subst_path(processDefines(defs)), suffix, env)