#NEWLINE# def is_parallel( l1 , l2 ) : #NEWLINE# #INDENT# 'Are two linear entities parallel?\n\n        Parameters\n        ==========\n\n        l1 : LinearEntity\n        l2 : LinearEntity\n\n        Returns\n        =======\n\n        True : if l1 and l2 are parallel,\n        False : otherwise.\n\n        See Also\n        ========\n\n        coefficients\n\n        Examples\n        ========\n\n        >>> from sympy import Point, Line\n        >>> p1, p2 = Point(0, 0), Point(1, 1)\n        >>> p3, p4 = Point(3, 4), Point(6, 7)\n        >>> l1, l2 = Line(p1, p2), Line(p3, p4)\n        >>> Line.is_parallel(l1, l2)\n        True\n\n        >>> p5 = Point(6, 6)\n        >>> l3 = Line(p3, p5)\n        >>> Line.is_parallel(l1, l3)\n        False\n\n        ' #NEWLINE# try : #NEWLINE# #INDENT# ( a1 , b1 , c1 ) = l1 . coefficients #NEWLINE# ( a2 , b2 , c2 ) = a2 . coefficients #NEWLINE# return bool ( ( simplify ( ( ( a1 * b2 ) - ( b1 * a2 ) ) ) == 0 ) ) #NEWLINE# #UNINDENT# except AttributeError : #NEWLINE# #INDENT# return False