@register.filter
def joinstrings(string_format, string_arguments):
    '''Template filters that perform string joins.
    
       Examples:
       1)
       var = '23'
       {{"I have eat %s apples today."|joinstrings:var}} -> "I have eat 23 apples today."
       
       2)
       var = [23, 45]   #or any iterable object (except string - see pt. 1) 
       {{"I have eat %d apples and %d pears today."|joinstrings:var}} -> "I have eat 23 apples and 45 pears today."

       3)
       It works even like that:
       var = 'Mouses'
       {% with 'My cat eat 5 %s today'|joinstrings:var|lower as info %}
        {{info}}
       {% endwith %}
    '''
    
    try:
        if hasattr(string_arguments, '__iter__'):
            return string_format%tuple(string_arguments)
        else:
            return string_format%string_arguments
    except:
        return string_format