How to display month name by number?

You'll need a custom template filter to convert the number into a month name. Pretty simple if you use the calendar module from the standard library:

import calendar

@register.filter
def month_name(month_number):
    return calendar.month_name[month_number]

Usage example: {{ 5|month_name }} will output May

you should use :

{{ datetimeobj|date:"F" }}

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