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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 handle_verification_form(form):
 """Handle email sending verification form."""

    form.process(formdata=request.form)

    if form.validate_on_submit():
        send_confirmation_instructions(current_user)
        # NOTE: Flash message.
        flash(_("Verification email sent."), category="success")