Thanks. I've found a description as well on GitHub:
Auto submit data URL format:
h**p://www.gmcmap.com/log2.asp?AID=UserAccountID&GID=GeigerCounterID&CPM=nCPM&ACPM=nACPM&uSV=nuSV
At least one reading of the data has to be submitted.
UserAccountID: user account ID. This ID is assigned once a user registration is completed.
GeigerCounterID: a global unique ID for each registered Geiger Counter.
nCPM: Count Per Minute reading from this Geiger Counter.
nACPM: Average Count Per Minute reading from this Geiger Counter(optional).
nuSv: uSv/h reading from this Geiger Counter(optional).
Example:
h**p://www.gmcmap.com/log2.asp?AID=1111111&GID=0123456789&CPM=15&ACPM=0&uSV=0
h**p://www.gmcmap.com/log2.asp?AID=1111111&GID=0123456789&CPM=15
Python code was tested, works ok, a point with CPM values appeared on a map.