# PythonCommand

Runs python code.

## user

Container for user-defined plugs. Nodes should never make their own plugs here, so users are free to do as they wish.

Input connections to upstream nodes which must be executed before this node.

Input connections to nodes which must be executed after this node, but which don’t need to be executed before downstream nodes.

Output connections to downstream nodes which must not be executed until after this node.

## dispatcher

Container for custom plugs which dispatchers use to control their behaviour.

## dispatcher.batchSize

Maximum number of frames to batch together when dispatching tasks. If the node requires sequence execution batchSize will be ignored.

## dispatcher.immediate

Causes this node to be executed immediately upon dispatch, rather than have its execution be scheduled normally by the dispatcher. For instance, when using the LocalDispatcher, the node will be executed immediately in the dispatching process and not in a background process as usual.

When a node is made immediate, all upstream nodes are automatically considered to be immediate too, regardless of their settings.

## command

The command to run. This may reference any of the variables by name, and also the node itself as self and the current Context as context.

## variables

An arbitrary set of variables which can be accessed via the variables dictionary within the python command.

## sequence

Calls the command once for each sequence, instead of once per frame. In this mode, an additional variable called frames is available to the command, containing a list of all frame numbers for which execution should be performed. The Context may be updated to reference any frame from this list, and accessing a variable returns the value for the current frame.

A typical structure for the command might look something like this :

# Do some one-time initialization
...
# Process all frames
for frame in frames :
context.setFrame( frame )
# Read variables after setting the frame to get
# the right values for that frame.
v = variables["v"]
...
# Do some one-time finalization
...