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docs/topics/gjp.md

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+# GJP
+
+GJP is a parameter commonly sent as `gjp` in requests. It is used for account authentication, and commonly sent with the `accountID` parameter. 
+
+## Encoding/Decoding
+
+The GJP is your account password XOR-encoded with key "37526", and then encoded with base64.
+
+To decode, take the GJP and decode it from base64, then XOR-encode it again (XOR encoding and decoding is identical).
+
+**The following code demonstrates this process programmatically:**
+
+<!-- tabs:start -->
+
+### **Python**
+
+```py
+import base64
+
+def encode_gjp(password: str) -> str:
+	# put it through the xor cipher with the key "37526")
+	encoded = xor_cipher(password, "37526")
+	# encode the password to base64
+	encoded_base64 = base64.b64encode(encoded.encode()).decode()
+  encoded_base64 = encoded_base64.replace("+", "-")
+  encoded_base64 = encoded_base64.replace("/", "_")
+
+	return encoded_base64
+
+def decode_gjp(gjp: str) -> str:
+	# decode the password from base64
+	decoded_base64 = base64.b64decode(gjp.encode()).decode()
+	# put it through the xor cipher with the key "37526")
+	decoded = xor_cipher(decoded_base64, "37526")
+
+	return decoded
+```
+
+<!-- tabs:end -->