add method from aurora

mth5/timeseries/spectre/helpers.py

@@ -349,3 +349,33 @@ def calibrate_stft_obj(
         # TODO: FIXME Sometimes raises a runtime warning due to DC term in calibration response = 0
         stft_obj[channel_id].data /= calibration_response
     return stft_obj
+
+
+def get_degenerate_fc_decimation(sample_rate: float) -> list:
+    """
+        TODO: consider placing this in mt_metadata.decimation.py
+
+    Makes a default fc_decimation list. WIP
+    This "degenerate" config will only operate on the first decimation level.
+    This is useful for testing.  It could also be used in future on an MTH5 stored time series in decimation
+    levels already as separate runs.
+
+    Parameters
+    ----------
+    sample_rate: float
+        The sample rate associated with the time-series to convert to spectrogram
+
+    Returns
+    -------
+    output: list
+        List has only one element which is of type FCDecimation, aka.
+
+    """
+    output = fc_decimations_creator(
+        sample_rate,
+        decimation_factors=[
+            1,
+        ],
+        max_levels=1,
+    )
+    return output