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public/py/sgp4/earth_gravity.py

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+"""Three earth-gravity models for use with SGP4."""
+
+from collections import namedtuple
+from sgp4.propagation import getgravconst
+
+EarthGravity = namedtuple(
+    'EarthGravity',
+    'tumin mu radiusearthkm xke j2 j3 j4 j3oj2',
+    )
+
+wgs72old = EarthGravity(*getgravconst('wgs72old'))
+wgs72 = EarthGravity(*getgravconst('wgs72'))
+wgs84 = EarthGravity(*getgravconst('wgs84'))