(subtrees)
return f
Prettyprints systems of nodes.

    Examples
    ========

    >>> from sympy.printing.tree import pprint_nodes
    >>> print(pprint_nodes(["a", "b1\\nb2", "c"]))
    +-a
    +-b1
    | b2
    +-c
Prettyprints systems of nodes.
Prettyprints systems of nodes .
def pprint_nodes(subtrees):
    """
    Prettyprints systems of nodes.

    Examples
    ========

    >>> from sympy.printing.tree import pprint_nodes
    >>> print(pprint_nodes(["a", "b1\\nb2", "c"]))
    +-a
    +-b1
    | b2
    +-c

    """
    def indent(s, type=1):
        x = s.split("\n")
        r = "+-%s\n" % x[0]
        for a in x[1:]:
            if a == "":
                continue
            if type == 1:
                r += "| %s\n" % a
            else:
                r += "  %s\n" % a
        return r
    if len(subtrees) == 0:
        return ""
    f = ""
    for a in subtrees[:-1]:
        f += indent(a)
    f += indent(subtrees[-1], 2)
    return f
def pprint_nodes ( subtrees ) : def indent ( s , type = 1 ) : x = s . split ( "\n" ) r = "+-%s\n" % x [ 0 ] for a in x [ 1 : ] : if a == "" : continue if type == 1 : r += "| %s\n" % a else : r += "  %s\n" % a return r if len ( subtrees ) == 0 : return "" f = "" for a in subtrees [ : - 1 ] : f += indent ( a ) f += indent ( subtrees [ - 1 ] , 2 ) return f