Remove `invert` option from kepler_io.read_kepler_light_curve().

Inversion should be done *after* fitting a normalization curve to the stellar variability and dividing it away. Doing it before normalizing may result in unintentionally reversing the inversion. Therefore we remove the option to do it at this point.

PiperOrigin-RevId: 207309650

research/astronet/light_curve_util/kepler_io.py

@@ -142,15 +142,12 @@ def kepler_filenames(base_dir,
   return filenames
 
 
-def read_kepler_light_curve(filenames,
-                            light_curve_extension="LIGHTCURVE",
-                            invert=False):
+def read_kepler_light_curve(filenames, light_curve_extension="LIGHTCURVE"):
   """Reads time and flux measurements for a Kepler target star.
 
   Args:
     filenames: A list of .fits files containing time and flux measurements.
     light_curve_extension: Name of the HDU 1 extension containing light curves.
-    invert: Whether to invert the flux measurements by multiplying by -1.
 
   Returns:
     all_time: A list of numpy arrays; the time values of the light curve.
@@ -171,9 +168,6 @@ def read_kepler_light_curve(filenames,
     time = time[valid_indices]
     flux = flux[valid_indices]
 
-    if invert:
-      flux *= -1
-
     if time.size:
       all_time.append(time)
       all_flux.append(flux)