As Wikipedia notes, "... SOAP ... is a protocol for exchanging XML-based messages ..." It's nominally language-independent (and platform-independent, encoding-aware, transport-neutral, ...).
Many Pythoneers are ... reserved about the complexities of and incoherent design of SOAP; Rob Riggs rants for many when he writes "... they invented SOAP for brainwashing software architects."
The page on WebServices says more.