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Given the following text description, write Python code to implement the functionality described below step by step
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Description:
 Geotransforms
May-June, 2018, Mauro Alberti, alberti.m65@gmail.com
1. Examples
Step1:  Forward and backward transformation examples
Step2:  calculating the X, Y geographic coordinate arrays
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Python Code:
from pygsf.spatial.rasters.geotransform import *
gt1 = GeoTransform(1500, 3000, 10, 10)
gt1
Explanation: Geotransforms
May-June, 2018, Mauro Alberti, alberti.m65@gmail.com
1. Examples
End of explanation
ijPixToxyGeogr(gt1, 0, 0)
xyGeogrToijPix(gt1, 1500, 3000)
ijPixToxyGeogr(gt1, 1, 1)
xyGeogrToijPix(gt1, 1510, 2990)
ijPixToxyGeogr(gt1, 10, 10)
xyGeogrToijPix(gt1, 1600, 3100)
Explanation: Forward and backward transformation examples
End of explanation
X, Y = gtToxyCellCenters(
    gt=gt1,
    num_rows=10,
    num_cols=5)
print(X)
print(Y)
Explanation: calculating the X, Y geographic coordinate arrays
End of explanation
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