Client.php, line 122: Call to undefined function GuzzleHttp\\Psr7\\stream_for()

[paianoa]

Line 122:
$request = $request->withBody(Psr7\stream_for(json_encode($bodyArray)));

Should be changed to:
$request = $request->withBody(Psr7\Utils::streamFor(json_encode($bodyArray)));

[PierreGranger]

Same here, after a composer update i've got the same issue.
The update shared by @paianoa resolves the issue.

The pull request here should be accepted :
9f5ac1b

[mghoneimy]

Addressed by #61