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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 load_file(self, file):
 """ Reads and loads given file into the editor. :param File: File to load. :type File: unicode :return: Method success. :rtype: bool """


        if not foundations.common.path_exists(file):
            raise foundations.exceptions.FileExistsError(
                "{0} | '{1}' file doesn't exists!".format(self.__class__.__name__,
                                                          file))

        LOGGER.debug("> Loading '{0}' file.".format(file))
        reader = foundations.io.File(file)
        self.setPlainText(reader.read())
        self.set_file(file)
        self.__set_document_signals()
        self.file_loaded.emit()
        return True