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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 find_in_data_path(filename):
 """Searches for a file within Fuel's data path. This function loops over all paths defined in Fuel's data path and returns the first path in which the file is found. Parameters filename : str Name of the file to find. Returns ------- file_path : str Path to the first file matching `filename` found in Fuel's data path. Raises ------ IOError If the file doesn't appear in Fuel's data path. """

    for path in config.data_path:
        path = os.path.expanduser(os.path.expandvars(path))
        file_path = os.path.join(path, filename)
        if os.path.isfile(file_path):
            return file_path
    raise IOError("{} not found in Fuel's data path".format(filename))