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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 read_array(self, infile, var_name):
 """Directly return a numpy array for a given variable name"""

        file_handle = self.read_cdf(infile)
        try:
            # return the data array
            return file_handle.variables[var_name][:]
        except KeyError:
            print("Cannot find variable: {0}".format(var_name))
            raise KeyError