Need to parse this landsat 7 metadata file (LE70230322000284EDC00_MTL.txt) for a specific scene to obtain input parameters SUN_ELEVATION and DOY:

GROUP = L1_METADATA_FILE
GROUP = METADATA_FILE_INFO
ORIGIN = "Image courtesy of the U.S. Geological Survey"
REQUEST_ID = "0101412026211_00196"
LANDSAT_SCENE_ID = "LE70230322000284EDC00"
FILE_DATE = 2014-12-03T03:44:34Z
STATION_ID = "EDC"
PROCESSING_SOFTWARE_VERSION = "LPGS_12.5.0"
DATA_CATEGORY = "NOMINAL"
END_GROUP = METADATA_FILE_INFO
GROUP = PRODUCT_METADATA
DATA_TYPE = "L1T"
ELEVATION_SOURCE = "GLS2000"
OUTPUT_FORMAT = "GEOTIFF"
EPHEMERIS_TYPE = "DEFINITIVE"
SPACECRAFT_ID = "LANDSAT_7"
SENSOR_ID = "ETM"
SENSOR_MODE = "SAM"
WRS_PATH = 023
WRS_ROW = 032
DATE_ACQUIRED = 2000-10-10
SCENE_CENTER_TIME = 16:25:50.4752115Z
CORNER_UL_LAT_PRODUCT = 41.29146
CORNER_UL_LON_PRODUCT = -90.34145
CORNER_UR_LAT_PRODUCT = 41.33905
CORNER_UR_LON_PRODUCT = -87.46493
CORNER_LL_LAT_PRODUCT = 39.31629
CORNER_LL_LON_PRODUCT = -90.24541
CORNER_LR_LAT_PRODUCT = 39.36068
CORNER_LR_LON_PRODUCT = -87.45153
CORNER_UL_PROJECTION_X_PRODUCT = 220200.000
CORNER_UL_PROJECTION_Y_PRODUCT = 4576500.000
CORNER_UR_PROJECTION_X_PRODUCT = 461100.000
CORNER_UR_PROJECTION_Y_PRODUCT = 4576500.000
CORNER_LL_PROJECTION_X_PRODUCT = 220200.000
CORNER_LL_PROJECTION_Y_PRODUCT = 4356900.000
CORNER_LR_PROJECTION_X_PRODUCT = 461100.000
CORNER_LR_PROJECTION_Y_PRODUCT = 4356900.000
PANCHROMATIC_LINES = 14641
PANCHROMATIC_SAMPLES = 16061
REFLECTIVE_LINES = 7321
REFLECTIVE_SAMPLES = 8031
THERMAL_LINES = 7321
THERMAL_SAMPLES = 8031
FILE_NAME_BAND_1 = "LE70230322000284EDC00_B1.TIF"
FILE_NAME_BAND_2 = "LE70230322000284EDC00_B2.TIF"
FILE_NAME_BAND_3 = "LE70230322000284EDC00_B3.TIF"
FILE_NAME_BAND_4 = "LE70230322000284EDC00_B4.TIF"
FILE_NAME_BAND_5 = "LE70230322000284EDC00_B5.TIF"
FILE_NAME_BAND_6_VCID_1 = "LE70230322000284EDC00_B6_VCID_1.TIF"
FILE_NAME_BAND_6_VCID_2 = "LE70230322000284EDC00_B6_VCID_2.TIF"
FILE_NAME_BAND_7 = "LE70230322000284EDC00_B7.TIF"
FILE_NAME_BAND_8 = "LE70230322000284EDC00_B8.TIF"
GROUND_CONTROL_POINT_FILE_NAME = "LE70230322000284EDC00_GCP.txt"
METADATA_FILE_NAME = "LE70230322000284EDC00_MTL.txt"
CPF_NAME = "L7CPF20001001_20001231.14"
END_GROUP = PRODUCT_METADATA
GROUP = IMAGE_ATTRIBUTES
CLOUD_COVER = 0.00
IMAGE_QUALITY = 9
SUN_AZIMUTH = 155.03337616
SUN_ELEVATION = 39.54882089
GROUND_CONTROL_POINTS_VERSION = 1
GROUND_CONTROL_POINTS_MODEL = 130
GEOMETRIC_RMSE_MODEL = 4.268
GEOMETRIC_RMSE_MODEL_Y = 3.089
GEOMETRIC_RMSE_MODEL_X = 2.945
END_GROUP = IMAGE_ATTRIBUTES
GROUP = MIN_MAX_RADIANCE
RADIANCE_MAXIMUM_BAND_1 = 191.600
RADIANCE_MINIMUM_BAND_1 = -6.200
RADIANCE_MAXIMUM_BAND_2 = 196.500
RADIANCE_MINIMUM_BAND_2 = -6.400
RADIANCE_MAXIMUM_BAND_3 = 152.900
RADIANCE_MINIMUM_BAND_3 = -5.000
RADIANCE_MAXIMUM_BAND_4 = 157.400
RADIANCE_MINIMUM_BAND_4 = -5.100
RADIANCE_MAXIMUM_BAND_5 = 31.060
RADIANCE_MINIMUM_BAND_5 = -1.000
RADIANCE_MAXIMUM_BAND_6_VCID_1 = 17.040
RADIANCE_MINIMUM_BAND_6_VCID_1 = 0.000
RADIANCE_MAXIMUM_BAND_6_VCID_2 = 12.650
RADIANCE_MINIMUM_BAND_6_VCID_2 = 3.200
RADIANCE_MAXIMUM_BAND_7 = 10.800
RADIANCE_MINIMUM_BAND_7 = -0.350
RADIANCE_MAXIMUM_BAND_8 = 243.100
RADIANCE_MINIMUM_BAND_8 = -4.700
END_GROUP = MIN_MAX_RADIANCE
GROUP = MIN_MAX_PIXEL_VALUE
QUANTIZE_CAL_MAX_BAND_1 = 255
QUANTIZE_CAL_MIN_BAND_1 = 1
QUANTIZE_CAL_MAX_BAND_2 = 255
QUANTIZE_CAL_MIN_BAND_2 = 1
QUANTIZE_CAL_MAX_BAND_3 = 255
QUANTIZE_CAL_MIN_BAND_3 = 1
QUANTIZE_CAL_MAX_BAND_4 = 255
QUANTIZE_CAL_MIN_BAND_4 = 1
QUANTIZE_CAL_MAX_BAND_5 = 255
QUANTIZE_CAL_MIN_BAND_5 = 1
QUANTIZE_CAL_MAX_BAND_6_VCID_1 = 255
QUANTIZE_CAL_MIN_BAND_6_VCID_1 = 1
QUANTIZE_CAL_MAX_BAND_6_VCID_2 = 255
QUANTIZE_CAL_MIN_BAND_6_VCID_2 = 1
QUANTIZE_CAL_MAX_BAND_7 = 255
QUANTIZE_CAL_MIN_BAND_7 = 1
QUANTIZE_CAL_MAX_BAND_8 = 255
QUANTIZE_CAL_MIN_BAND_8 = 1
END_GROUP = MIN_MAX_PIXEL_VALUE
GROUP = PRODUCT_PARAMETERS
CORRECTION_GAIN_BAND_1 = "CPF"
CORRECTION_GAIN_BAND_2 = "CPF"
CORRECTION_GAIN_BAND_3 = "CPF"
CORRECTION_GAIN_BAND_4 = "CPF"
CORRECTION_GAIN_BAND_5 = "CPF"
CORRECTION_GAIN_BAND_6_VCID_1 = "CPF"
CORRECTION_GAIN_BAND_6_VCID_2 = "CPF"
CORRECTION_GAIN_BAND_7 = "CPF"
CORRECTION_GAIN_BAND_8 = "CPF"
CORRECTION_BIAS_BAND_1 = "INTERNAL_CALIBRATION"
CORRECTION_BIAS_BAND_2 = "INTERNAL_CALIBRATION"
CORRECTION_BIAS_BAND_3 = "INTERNAL_CALIBRATION"
CORRECTION_BIAS_BAND_4 = "INTERNAL_CALIBRATION"
CORRECTION_BIAS_BAND_5 = "INTERNAL_CALIBRATION"
CORRECTION_BIAS_BAND_6_VCID_1 = "INTERNAL_CALIBRATION"
CORRECTION_BIAS_BAND_6_VCID_2 = "INTERNAL_CALIBRATION"
CORRECTION_BIAS_BAND_7 = "INTERNAL_CALIBRATION"
CORRECTION_BIAS_BAND_8 = "INTERNAL_CALIBRATION"
GAIN_BAND_1 = "H"
GAIN_BAND_2 = "H"
GAIN_BAND_3 = "H"
GAIN_BAND_4 = "H"
GAIN_BAND_5 = "H"
GAIN_BAND_6_VCID_1 = "L"
GAIN_BAND_6_VCID_2 = "H"
GAIN_BAND_7 = "H"
GAIN_BAND_8 = "L"
GAIN_CHANGE_BAND_1 = "HH"
GAIN_CHANGE_BAND_2 = "HH"
GAIN_CHANGE_BAND_3 = "HH"
GAIN_CHANGE_BAND_4 = "HH"
GAIN_CHANGE_BAND_5 = "HH"
GAIN_CHANGE_BAND_6_VCID_1 = "LL"
GAIN_CHANGE_BAND_6_VCID_2 = "HH"
GAIN_CHANGE_BAND_7 = "HH"
GAIN_CHANGE_BAND_8 = "LL"
GAIN_CHANGE_SCAN_BAND_1 = 0
GAIN_CHANGE_SCAN_BAND_2 = 0
GAIN_CHANGE_SCAN_BAND_3 = 0
GAIN_CHANGE_SCAN_BAND_4 = 0
GAIN_CHANGE_SCAN_BAND_5 = 0
GAIN_CHANGE_SCAN_BAND_6_VCID_1 = 0
GAIN_CHANGE_SCAN_BAND_6_VCID_2 = 0
GAIN_CHANGE_SCAN_BAND_7 = 0
GAIN_CHANGE_SCAN_BAND_8 = 0
END_GROUP = PRODUCT_PARAMETERS
GROUP = RADIOMETRIC_RESCALING
RADIANCE_MULT_BAND_1 = 0.779
RADIANCE_MULT_BAND_2 = 0.799
RADIANCE_MULT_BAND_3 = 0.622
RADIANCE_MULT_BAND_4 = 0.640
RADIANCE_MULT_BAND_5 = 0.126
RADIANCE_MULT_BAND_6_VCID_1 = 0.067
RADIANCE_MULT_BAND_6_VCID_2 = 0.037
RADIANCE_MULT_BAND_7 = 0.044
RADIANCE_MULT_BAND_8 = 0.976
RADIANCE_ADD_BAND_1 = -6.97874
RADIANCE_ADD_BAND_2 = -7.19882
RADIANCE_ADD_BAND_3 = -5.62165
RADIANCE_ADD_BAND_4 = -5.73976
RADIANCE_ADD_BAND_5 = -1.12622
RADIANCE_ADD_BAND_6_VCID_1 = -0.06709
RADIANCE_ADD_BAND_6_VCID_2 = 3.16280
RADIANCE_ADD_BAND_7 = -0.39390
RADIANCE_ADD_BAND_8 = -5.67559
END_GROUP = RADIOMETRIC_RESCALING
GROUP = PROJECTION_PARAMETERS
MAP_PROJECTION = "UTM"
DATUM = "WGS84"
ELLIPSOID = "WGS84"
UTM_ZONE = 16
GRID_CELL_SIZE_PANCHROMATIC = 15.00
GRID_CELL_SIZE_REFLECTIVE = 30.00
GRID_CELL_SIZE_THERMAL = 30.00
ORIENTATION = "NORTH_UP"
RESAMPLING_OPTION = "CUBIC_CONVOLUTION"
END_GROUP = PROJECTION_PARAMETERS
END_GROUP = L1_METADATA_FILE
END