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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 send_login():
 """View function that sends login instructions for passwordless login"""


    form_class = _security.passwordless_login_form

    if request.is_json:
        form = form_class(MultiDict(request.get_json()))
    else:
        form = form_class()

    if form.validate_on_submit():
        send_login_instructions(form.user)
        if not request.is_json:
            do_flash(*get_message('LOGIN_EMAIL_SENT', email=form.user.email))

    if request.is_json:
        return _render_json(form)

    return _security.render_template(config_value('SEND_LOGIN_TEMPLATE'),
                                     send_login_form=form,
                                     **_ctx('send_login'))