Example of a python function for normalizing Japanese local phone number formats to E.164 using the incredible python port of Google's libphonenumber project: https://github.com/daviddrysdale/python-phonenumbers

japan_format.py

import phonenumbers as ph

def japan_format(phone_number, country_code='JP'):
    """
    Converts local Japanese formatted number to E.164 format

    Arguments:
    phone_number -- A Japanese phone number in any format as a string

    >>> japan_format("080-1234-5678")
    u'+818012345678'

    >>> japan_format("03.1234.5678")
    u'+81312345678'

    >>> japan_format("9012345678")
    u'+819012345678'

    >>> japan_format("+81 70 1234 5678")
    u'+817012345678'

    """
    number_object = ph.parse(phone_number, region=country_code)
    return ph.format_number(number_object, ph.PhoneNumberFormat.E164)

if __name__ == "__main__":
    import doctest
    doctest.testmod()