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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 to_struct_file(self, f):
 """ write the Vario2d to a PEST-style structure file Parameters f : (str or file handle) item to write to """

        if isinstance(f, str):
            f = open(f,'w')
        f.write("VARIOGRAM {0}\n".format(self.name))
        f.write("  VARTYPE {0}\n".format(self.vartype))
        f.write("  A {0}\n".format(self.a))
        f.write("  ANISOTROPY {0}\n".format(self.anisotropy))
        f.write("  BEARING {0}\n".format(self.bearing))
        f.write("END VARIOGRAM\n\n")