Dgp2Dcp canonicalizer for the 1-x atom

Dgp2Dcp.one_minus_pos_canon(expr, args)

## Arguments

expr

An Expression object

args

A list of values for the expr variable

## Value

A canonicalization of the 1-x with 0 < x < 1 atom of a DGP expression, where the returned expression is the transformed DCP equivalent.