''' Purpose: better experience functional development

    Buddies (if any):
'''

# necessary import

def future_me( age, y ) :
    ''' Function future_me( a, y ): how old a person whose now a years-old will be
        in year y
    '''

    pass

# --------------------------------------------------------------------

def manhattan_distance( a1, s1, a2, s2 ) :
    ''' Function manhattan_distance( a1, s1, a2, s2 ): returns the
            approximate distance in miles between a person at the corner
            avenue a1 and street s1 in Manhattan and a person at the
            corner of avenue a2 and street s2 also in Manhattan.
    '''

    pass



# --------------------------------------------------------------------

def relate( x, y ) :
    ''' Function relate( x, y ): returns 'comes before', 'is equal to',
            or 'comes after', depending on the alphabetical relationship
            between strings x and y .
    '''

    pass




# --------------------------------------------------------------------

def youngest( y ) :
    ''' Function youngest( y ): returns the youngest acceptable integer age for
            a y-year old to date; i.e., the age must be at least seven years
            older than half of a y-year old
    '''

    pass



# --------------------------------------------------------------------

def is_dateable( y1, y2 ) :
    ''' Function is_dateable( y1, y2 ): returns True or False whether
            a y2-year old is an acceptably-aged date for a y1-year old.
    '''

    pass



# --------------------------------------------------------------------

def mutually_dateable( y1, y2 ) :
    ''' Function mutually_dateable( y1, y2 ): returns True or False
            whether both a y2-year old is an acceptably-aged date
            for a y1-year old and vice-versa.
    '''

    pass




# --------------------------------------------------------------------

def middle( s ) :
    ''' Function middle( s ):
            If the length of s is odd, the function returns the middle
            character of s; otherwise, the function returns the two middle
            characters of s.
    '''

    pass