added regex tutorial

Author: x4nth055

README.md

@@ -95,6 +95,7 @@ This is a repository of all the tutorials of [The Python Code](https://www.thepy
     - [How to Read Emails in Python](https://www.thepythoncode.com/article/reading-emails-in-python). ([code](python-standard-library/reading-email-messages))
     - [How to Download and Upload Files in FTP Server using Python](https://www.thepythoncode.com/article/download-and-upload-files-in-ftp-server-using-python). ([code](python-standard-library/download-and-upload-files-in-ftp))
     - [How to Work with JSON Files in Python](https://www.thepythoncode.com/article/working-with-json-files-in-python). ([code](python-standard-library/working-with-json))
+    - [How to Use Regular Expressions in Python](https://www.thepythoncode.com/article/work-with-regular-expressions-in-python). ([code](python-standard-library/regular-expressions))
 
 - ### [Using APIs](https://www.thepythoncode.com/topic/using-apis-in-python)
     - [How to Automate your VPS or Dedicated Server Management in Python](https://www.thepythoncode.com/article/automate-veesp-server-management-in-python). ([code](general/automating-server-management))

python-standard-library/regular-expressions/README.md

@@ -0,0 +1 @@
+# [How to Use Regular Expressions in Python](https://www.thepythoncode.com/article/work-with-regular-expressions-in-python)

python-standard-library/regular-expressions/finditer.py

@@ -0,0 +1,30 @@
+import re
+
+# fake ipconfig output
+example_text = """
+Ethernet adapter Ethernet:
+
+   Media State . . . . . . . . . . . : Media disconnected
+   Physical Address. . . . . . . . . : 88-90-E6-28-35-FA
+
+Ethernet adapter Ethernet 2:
+
+   Physical Address. . . . . . . . . : 04-00-4C-4F-4F-60
+   Autoconfiguration IPv4 Address. . : 169.254.204.56(Preferred)
+
+Wireless LAN adapter Local Area Connection* 2:
+
+   Media State . . . . . . . . . . . : Media disconnected
+   Physical Address. . . . . . . . . : B8-21-5E-D3-66-98
+
+Wireless LAN adapter Wi-Fi:
+
+   Physical Address. . . . . . . . . : A0-00-79-AA-62-74
+   IPv4 Address. . . . . . . . . . . : 192.168.1.101(Preferred)
+   Default Gateway . . . . . . . . . : 192.168.1.1
+"""
+# regex for MAC address
+mac_address_regex = r"([0-9A-Fa-f]{2}[:-]){5}([0-9A-Fa-f]{2})"
+# iterate over matches and extract MAC addresses
+extracted_mac_addresses = [ m.group(0) for m in re.finditer(mac_address_regex, example_text) ]
+print(extracted_mac_addresses)

python-standard-library/regular-expressions/match.py

@@ -0,0 +1,8 @@
+import re # stands for regular expression 
+# a regular expression for validating a password
+match_regex = r"^(?=.*[0-9]).{8,}$"
+# a list of example passwords
+passwords = ["pwd", "password", "password1"]
+for pwd in passwords:
+    m = re.match(match_regex, pwd)
+    print(f"Password: {pwd}, validate password strength: {bool(m)}")

python-standard-library/regular-expressions/search.py

@@ -0,0 +1,18 @@
+import re
+
+# part of ipconfig output
+example_text = """
+Wireless LAN adapter Wi-Fi:
+
+   Connection-specific DNS Suffix  . :
+   Link-local IPv6 Address . . . . . : fe80::380e:9710:5172:caee%2
+   IPv4 Address. . . . . . . . . . . : 192.168.1.100
+   Subnet Mask . . . . . . . . . . . : 255.255.255.0
+   Default Gateway . . . . . . . . . : 192.168.1.1
+"""
+
+# regex for IPv4 address
+ip_address_regex = r"((25[0-5]|(2[0-4]|1[0-9]|[1-9]|)[0-9])(\.(?!$)|$)){4}"
+# use re.search() method to get the match object
+match = re.search(ip_address_regex, example_text)
+print(match)

python-standard-library/regular-expressions/sub.py

@@ -0,0 +1,16 @@
+import re
+
+# a basic regular expression for email matching
+email_regex = r"[a-zA-Z0-9_.+-]+@[a-zA-Z0-9-]+\.[a-zA-Z0-9-.]+"
+# example text to test with
+example_text = """
+Subject: This is a text email!
+From: John Doe <[email protected]>
+Some text here!
+===============================
+Subject: This is another email!
+From: Abdou Rockikz <[email protected]>
+Some other text!
+"""
+# substitute any email found with [email protected]
+print(re.sub(email_regex, "[email protected]", example_text))