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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 _attempt_to_extract_idd(self):
 """Extracts IDD and plus sign to self._prefix_before_national_number when they are available, and places the remaining input into _national_number. Returns True when accrued_input_without_formatting begins with the plus sign or valid IDD for default_country. """

        international_prefix = re.compile(unicod("\\") + _PLUS_SIGN + unicod("|") +
                                          (self._current_metadata.international_prefix or U_EMPTY_STRING))
        idd_match = international_prefix.match(self._accrued_input_without_formatting)
        if idd_match:
            self._is_complete_number = True
            start_of_country_calling_code = idd_match.end()
            self._national_number = self._accrued_input_without_formatting[start_of_country_calling_code:]
            self._prefix_before_national_number = self._accrued_input_without_formatting[:start_of_country_calling_code]
            if self._accrued_input_without_formatting[0] != _PLUS_SIGN:
                self._prefix_before_national_number += _SEPARATOR_BEFORE_NATIONAL_NUMBER
            return True
        return False