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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 write_gct(df, file_path):
 """ Writes the provided DataFrame to a GCT file. Assumes that the DataFrame matches the structure of those produced by the GCT() function in this library :param df: :param file_path: :return: """

    with open(file_path, 'w') as file:
        file.write('#1.2\n' + str(len(df.index)) + '\t' + str(len(df.columns)) + '\n')
        df.to_csv(file, sep='\t', mode='w+')