def mean(num_lst):
    """
    calculations the mean of a list of numbers

    Parameters
    ----------
    num_lst: list of int or float
    List of numbers to calculate the average of

    Returns
    -------
    float of the average/mean of num_lst
    
    
    Examples
    --------
    >>> mean([1,2,3,4,5])
    3.0
    """
    num = 0.0
    for i in num_lst:
        num += i
    num = num / len(num_lst)

    return num