Python





```handlebars
匹配特定字符串：
只能输入长度为3的字符："^.{3}$"。
只能输入由26个英文字母组成的字符串："^[A-Za-z]+$"。
只能输入由26个大写英文字母组成的字符串："^[A-Z]+$"。
只能输入由26个小写英文字母组成的字符串："^[a-z]+$"。
只能输入由数字和26个英文字母组成的字符串："^[A-Za-z0-9]+$"。
只能输入由数字、26个英文字母或者下划线组成的字符串："^\w+$"。
```

python 正则表达式 匹配任意长度英文字母

文件：




```handlebars
,filename,filesize
0,data_20210416.tgz,4885254
1,data_20210417.tgz,4548204
```

如果：

```handlebars
df = pd.read_csv(logcsv)
```

那么：

![在这里插入图片描述](/static/img/images/00516.png)



如果：
```handlebars
df = pd.read_csv(logcsv,index_col=0)
```

那么：

![在这里插入图片描述](/static/img/images/00517.png)

python pandas read_csv 丢弃索引 Unnamed: 0 用起索引

让header等于None即可




```handlebars
df = pd.read_csv(filename, encoding='gbk', header=None)
df.columns=['calc_time','data_date','station_id','pm25_value','pm10_value','co_value','no2_value','so2_value','o3_1h_value','o3_8h_value']
```

有表头的时候这样做会报错。

pandas header 无表头 数据读取 python

Python





```python
import xml.etree.ElementTree as ET
from xml.etree.ElementTree import tostring
from xml.etree.ElementTree import Element
from io import BytesIO
root = Element("tag")
child = Element("child1", attrib={"jh": "123", "oi": "12312"})
child.text="dasd"
child2 = Element("child2", attrib={"jh": "123"})
child2.text="dasd"
root.append(child)
root.append(child2)
# print(tostring(root, encoding='utf8', method='xml').decode())
et = ET.ElementTree(root)
f = BytesIO()
et.write(f, encoding='utf-8', xml_declaration=True)
print(f.getvalue().decode())  # your XML file, encoded as UTF-8
```

写入到文件
```python
tree = ET.ElementTree(root)
tree.write("output.xml", encoding="utf-8", xml_declaration=True)  #保存时无缩进，添加缩进需要借用dom
```

带缩进地写入到文件
```python
import xml.etree.ElementTree as ET
from xml.dom import minidom
def saveXML(root, filename, indent="\t", newl="\n", encoding="utf-8"):
    rawText = ET.tostring(root)
    dom = minidom.parseString(rawText)
    with open(filename, 'w') as f:
        dom.writexml(f, "", indent, newl, encoding)
```

xml 生成 ＜?xml version=‘1.0‘ encoding=‘utf-8‘?＞ python

[https://stackoverflow.com/questions/39276248/creating-an-md5-hash-of-a-zipfile](https://stackoverflow.com/questions/39276248/creating-an-md5-hash-of-a-zipfile)




```python
import hashlib
def get_MD5(file_path):
    chunk_size = 8192
    h = hashlib.md5()
    with open(file_path, 'rb') as f:
        while True:
            chunk = f.read(chunk_size)  # 文件太大就需要chunk_size
            if len(chunk):
                h.update(chunk)
            else:
                break
    return h.hexdigest()
print(get_MD5('./apptest.py'))
print(get_MD5('./test.zip'))
```

文件小的时候一句话就好：

```python
file = "./cls94_20230515_V1.0.6.mnn"
# 打印md5
import hashlib
print(hashlib.md5(open(file, 'rb').read()).hexdigest())
```