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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 fromexcel(cls, path, sheet_name_or_num=0, headers=None):
 """ Constructs a new DataTable from an Excel file. Specify sheet_name_or_number to load that specific sheet. Headers will be inferred automatically, but if you'd prefer to load only a subset of all the headers, pass in a list of the headers you'd like as `headers`. --- Alternatively, it's quite simple to: reader = ExcelReader('myfile.xls') reader.change_sheet('default') data = DataTable(reader) """

        reader = ExcelRW.UnicodeDictReader(path, sheet_name_or_num)
        return cls(reader, headers=headers)