I have written this code for a form I was working on.

<div class="col-md-6"><label class="labels">Doğum Günü:</label><input method="POST"name="birtdate" class="form-control" {% if student.birtdate%} type="text"value="{{student.birtdate}}" onfocus="(this.type='date')"onblur="(this.type='text')" {%else %}type="date" {% endif %}></div></div>

It should show the initial value when blur and turn into a date field when focused. The problem is when I click on it and then click away it shows an empty value. I need to somehow check that and make it not change the value if the input is empty. How can I do that?