def isalnum(text):
    """
    Checks if all characters in ``text`` are alphanumeric and there is at least one character
    
    A character c is alphanumeric if one of the following returns True: :func:`isalpha`, 
    :func:`isdecimal`,:func:`isdigit`, or, :func:`isnumeric`.
    
    :param text: The string to check
    :type text:  ``str``
    
    :return: True if all characters in ``text`` are alphanumeric and there is at least one character, False otherwise.
    :rtype:  ``bool``
    """
    assert isinstance(text,str), '%s is not a string' % text
    return text.isalnum()