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Solve the following problem using Python, implementing the functions described below, one line at a time
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Description:
 def point_line_distance(point, start, end):
 """ Distance from a point to a line, formed by two points Args: point (:obj:`Point`) start (:obj:`Point`):
 line point end (:obj:`Point`):
 line point Returns: float: distance to line, in degrees """

    if start == end:
        return distance(point, start)
    else:
        un_dist = abs(
            (end.lat-start.lat)*(start.lon-point.lon) - (start.lat-point.lat)*(end.lon-start.lon)
        )
        n_dist = sqrt(
            (end.lat-start.lat)**2 + (end.lon-start.lon)**2
        )
        if n_dist == 0:
            return 0
        else:
            return un_dist / n_dist