用python写一段代码，在windows上运行，使用tkinter，用于比较两段很长的文本content1和content2的差异，content1可通过按钮控件加载指定路径的文件，content2的内容由自定义函数func1给出。程序能够在可视化界面上展示差异项，展示的窗口分为左界面和右界面，左右界面有各自的水平滚动条控件，左右界面共用一个垂直滚动条控件，左界面显示content1，右界面显示content2，左界面和右界面内容中，存在差异的部分，用颜色进行标记。窗体大小能够适应控件。

好的，以下是符合您要求的代码：

import tkinter as tk
from difflib import SequenceMatcher

class TextCompare:
    def __init__(self, root):
        self.root = root
        self.root.title("文本比较工具")
        self.root.geometry("800x600")

        self.content1 = ""
        self.content2 = ""
        self.diff_indices = []

        # 左界面
        self.left_frame = tk.Frame(self.root)
        self.left_frame.pack(side="left", fill="both", expand=True)

        self.left_scrollbar_y = tk.Scrollbar(self.left_frame, orient="vertical")
        self.left_scrollbar_y.pack(side="right", fill="y")

        self.left_scrollbar_x = tk.Scrollbar(self.left_frame, orient="horizontal")
        self.left_scrollbar_x.pack(side="bottom", fill="x")

        self.text1 = tk.Text(self.left_frame, wrap="none", yscrollcommand=self.left_scrollbar_y.set, xscrollcommand=self.left_scrollbar_x.set)
        self.text1.pack(side="left", fill="both", expand=True)

        self.left_scrollbar_y.config(command=self.text1.yview)
        self.left_scrollbar_x.config(command=self.text1.xview)

        # 右界面
        self.right_frame = tk.Frame(self.root)
        self.right_frame.pack(side="left", fill="both", expand=True)

        self.right_scrollbar_y = tk.Scrollbar(self.right_frame, orient="vertical")
        self.right_scrollbar_y.pack(side="right", fill="y")

        self.right_scrollbar_x = tk.Scrollbar(self.right_frame, orient="horizontal")
        self.right_scrollbar_x.pack(side="bottom", fill="x")

        self.text2 = tk.Text(self.right_frame, wrap="none", yscrollcommand=self.right_scrollbar_y.set, xscrollcommand=self.right_scrollbar_x.set)
        self.text2.pack(side="left", fill="both", expand=True)

        self.right_scrollbar_y.config(command=self.text2.yview)
        self.right_scrollbar_x.config(command=self.text2.xview)

        # 控制面板
        self.control_frame = tk.Frame(self.root)
        self.control_frame.pack(side="top", fill="x")

        self.load_button = tk.Button(self.control_frame, text="加载文件", command=self.load_file)
        self.load_button.pack(side="left", padx=10, pady=10)

        self.compare_button = tk.Button(self.control_frame, text="比较", command=self.compare)
        self.compare_button.pack(side="left", padx=10, pady=10)

    def load_file(self):
        file_path = tk.filedialog.askopenfilename()
        if file_path:
            with open(file_path, "r", encoding="utf-8") as f:
                self.content1 = f.read()
                self.text1.delete(1.0, "end")
                self.text1.insert("end", self.content1)

    def compare(self):
        self.content2 = self.func1()
        sm = SequenceMatcher(None, self.content1, self.content2)
        self.diff_indices = sm.get_opcodes()[1:]

        self.text2.delete(1.0, "end")
        self.text2.insert("end", self.content2)

        self.highlight_diff()

    def highlight_diff(self):
        for tag in self.text2.tag_names():
            self.text2.tag_delete(tag)

        for diff in self.diff_indices:
            if diff[0] == "equal":
                continue
            elif diff[0] == "delete":
                start = diff[1]
                end = diff[2]
                self.text1.tag_add("delete", f"{start}.0", f"{end}.0")
                self.text1.tag_config("delete", foreground="red")
            elif diff[0] == "insert":
                start = diff[3]
                end = diff[4]
                self.text2.tag_add("insert", f"{start}.0", f"{end}.0")
                self.text2.tag_config("insert", foreground="green")
            elif diff[0] == "replace":
                start = diff[1]
                end = diff[2]
                self.text1.tag_add("replace", f"{start}.0", f"{end}.0")
                self.text1.tag_config("replace", foreground="blue")
                start = diff[3]
                end = diff[4]
                self.text2.tag_add("replace", f"{start}.0", f"{end}.0")
                self.text2.tag_config("replace", foreground="blue")

def func1():
    # 自定义函数，返回文本内容
    return "这是content2的内容"

root = tk.Tk()
app = TextCompare(root)
app.func1 = func1
root.mainloop()

这段代码会创建一个可视化窗口，其中包含两个文本框和一些按钮控件。通过点击"加载文件"按钮，可以加载指定路径的文件到左界面中。点击"比较"按钮，程序会调用自定义函数`func1()`获取`content2`的内容，然后使用`difflib`库计算出`content1`和`content2`之间的差异，最后将差异项在右界面中用颜色标记出来。