sublime安装repl插件后，根据网上教程进行绑定快捷键，屡屡失败。（我的版本是Sublime Text3.3）
网上教程一般是说，Default.sublime-commands文件内为绑定模板（步骤：Preferences–>Browse Packages–>SublimeREPL文件夹–>config文件夹–>Python文件夹–>Default.sublime-commands(以文本格式打开)）。
然而于我的小sublime而言没有卵用，经过尝试，我选择了同一文件夹下的Main.sublime-menu文件作为绑定模板，神奇地绑定成功。
原文件如下（文件路径“sublimeREPL/config/Python/Main.sublime-menu”）

[
     {
        "id": "tools",
        "children":
        [{
            "caption": "SublimeREPL",
            "mnemonic": "R",
            "id": "SublimeREPL",
            "children":
            [
                {"caption": "Python",
                "id": "Python",

                 "children":[
                    {"command": "repl_open",
                     "caption": "Python",
                     "id": "repl_python",
                     "mnemonic": "P",
                     "args": {
                        "type": "subprocess",
                        "encoding": "utf8",
                        "cmd": ["python", "-i", "-u"],
                        "cwd": "$file_path",
                        "syntax": "Packages/Python/Python.tmLanguage",
                        "external_id": "python",
                        "extend_env": {"PYTHONIOENCODING": "utf-8"}
                        }
                    },
                    {"command": "python_virtualenv_repl",
                     "id": "python_virtualenv_repl",
                     "caption": "Python - virtualenv"},
                    {"command": "repl_open",
                     "caption": "Python - PDB current file",
                     "id": "repl_python_pdb",
                     "mnemonic": "D",
                     "args": {
                        "type": "subprocess",
                        "encoding": "utf8",
                        "cmd": ["python", "-i", "-u", "-m", "pdb", "$file_basename"],
                        "cwd": "$file_path",
                        "syntax": "Packages/Python/Python.tmLanguage",
                        "external_id": "python",
                        "extend_env": {"PYTHONIOENCODING": "utf-8"}
                        }
                    },
                    {"command": "repl_open",
                     "caption": "Python - RUN current file",
                     "id": "repl_python_run",
                     "mnemonic": "R",
                     "args": {
                        "type": "subprocess",
                        "encoding": "utf8",
                        "cmd": ["python", "-u", "$file_basename"],
                        "cwd": "$file_path",
                        "syntax": "Packages/Python/Python.tmLanguage",
                        "external_id": "python",
                        "extend_env": {"PYTHONIOENCODING": "utf-8"}
                        }
                    },
                    {"command": "repl_open",
                     "caption": "Python - IPython",
                     "id": "repl_python_ipython",
                     "mnemonic": "I",
                     "args": {
                        "type": "subprocess",
                        "encoding": "utf8",
                        "autocomplete_server": true,
                        "cmd": {
                            "osx": ["python", "-u", "${packages}/SublimeREPL/config/Python/ipy_repl.py"],
                            "linux": ["python", "-u", "${packages}/SublimeREPL/config/Python/ipy_repl.py"],
                            "windows": ["python", "-u", "${packages}/SublimeREPL/config/Python/ipy_repl.py"]
                        },
                        "cwd": "$file_path",
                        "syntax": "Packages/Python/Python.tmLanguage",
                        "external_id": "python",
                        "extend_env": {
                            "PYTHONIOENCODING": "utf-8",
                            "SUBLIMEREPL_EDITOR": "$editor"
                        }
                    }
                    }
                ]}
            ]
        }]
    }
]

我完全是根据找不同和找相似的方法（对不起我太无知），猜想不同的caption对应不同功能的绑定。我要绑定的是“Python - RUN current file”，选择对应的花括号内的代码。我想绑定到f5键，所以开头加上代码"keys"：[“f5”]，最终代码为：

[
	{
	"keys": ["f5"],
	"command": "repl_open",
	"caption": "Python - RUN current file",
	"id": "repl_python_run",
	"mnemonic": "R",
	"args": 
		{
		"type": "subprocess",
		"encoding": "utf8",
		"cmd": ["python", "-u", "$file_basename"],
		"cwd": "$file_path",
		"syntax": "Packages/Python/Python.tmLanguage",
		"external_id": "python",
		"extend_env": {"PYTHONIOENCODING": "utf-8"}
		}
	}
]

复制以上代码，粘贴到Preferences–>Key Bindings User

亲测有效，不明所以。如果有大佬明白，跪求赐教。或者等我弄明白了，再来更新文章。