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Solve the following problem using Python, implementing the functions described below, one line at a time
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Description:
 def writevrt(out_csv,srs='EPSG:4326',x='field_1',y='field_2'):
 """ Write out a vrt to accompany a csv of points """

    out_vrt = os.path.splitext(out_csv)[0]+'.vrt'
    out_csv = os.path.split(out_csv)[-1]
    f = open(out_vrt, 'w')
    f.write('<OGRVRTDataSource>\n')
    f.write('   <OGRVRTLayer name="%s">\n' % os.path.splitext(out_csv)[0])
    f.write('        <SrcDataSource>%s</SrcDataSource>\n' % out_csv)
    f.write('        <GeometryType>wkbPoint</GeometryType>\n')
    f.write('        <LayerSRS>%s</LayerSRS>\n' % srs)
    f.write('        <GeometryField encoding="PointFromColumns" x="%s" y="%s"/>\n' % (x, y))
    f.write('    </OGRVRTLayer>\n')
    f.write('</OGRVRTDataSource>\n')
    f.close()