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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 _maybe_process_deprecations(r, how=None, fill_method=None, limit=None):
 """ Potentially we might have a deprecation warning, show it but call the appropriate methods anyhow. """


    if how is not None:

        # .resample(..., how='sum')
        if isinstance(how, str):
            method = "{0}()".format(how)

            # .resample(..., how=lambda x: ....)
        else:
            method = ".apply(<func>)"

        # if we have both a how and fill_method, then show
        # the following warning
        if fill_method is None:
            warnings.warn("how in .resample() is deprecated\n"
                          "the new syntax is "
                          ".resample(...).{method}".format(
                              method=method),
                          FutureWarning, stacklevel=3)
        r = r.aggregate(how)

    if fill_method is not None:

        # show the prior function call
        method = '.' + method if how is not None else ''

        args = "limit={0}".format(limit) if limit is not None else ""
        warnings.warn("fill_method is deprecated to .resample()\n"
                      "the new syntax is .resample(...){method}"
                      ".{fill_method}({args})".format(
                          method=method,
                          fill_method=fill_method,
                          args=args),
                      FutureWarning, stacklevel=3)

        if how is not None:
            r = getattr(r, fill_method)(limit=limit)
        else:
            r = r.aggregate(fill_method, limit=limit)

    return r