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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 mailto(to, cc=None, bcc=None, subject=None, body=None):
 """ Generate and run mailto. :type to: string :param to: The recipient email address. :type cc: string :param cc: The recipient to copy to. :type bcc: string :param bcc: The recipient to blind copy to. :type subject: string :param subject: The subject to use. :type body: string :param body: The body content to use. """


    mailurl = 'mailto:' + str(to)
    if cc is None and bcc is None and subject is None and body is None:
        return str(mailurl)
    mailurl += '?'
    if cc is not None:
        mailurl += 'cc=' + str(cc)
        added = True
    added = False
    if bcc is not None:
        if added is True:
            mailurl += '&'
        mailurl += 'bcc=' + str(cc)
        added = True
    if subject is not None:
        if added is True:
            mailurl += '&'
        mailurl += 'subject=' + str(subject)
        added = True
    if body is not None:
        if added is True:
            mailurl += '&'
        mailurl += 'body=' + str(body)
        added = True
    return mailurl