1414
1515
1616@six .add_metaclass (ABCMeta )
17- class DependencyResolver (Dictifiable , object ):
17+ class DependencyResolver (Dictifiable ):
1818 """Abstract description of a technique for resolving container images for tool execution."""
1919
2020 # Keys for dictification.
@@ -43,7 +43,7 @@ def resolve(self, requirement, **kwds):
4343 """
4444
4545
46- class MultipleDependencyResolver :
46+ class MultipleDependencyResolver ( object ) :
4747 """Variant of DependencyResolver that can optionally resolve multiple dependencies together."""
4848
4949 @abstractmethod
@@ -62,7 +62,7 @@ def resolve_all(self, requirements, **kwds):
6262
6363
6464@six .add_metaclass (ABCMeta )
65- class ListableDependencyResolver :
65+ class ListableDependencyResolver ( object ) :
6666 """ Mix this into a ``DependencyResolver`` and implement to indicate
6767 the dependency resolver can iterate over its dependencies and generate
6868 requirements.
@@ -78,7 +78,7 @@ def _to_requirement(self, name, version=None):
7878 return ToolRequirement (name = name , type = "package" , version = version )
7979
8080
81- class MappableDependencyResolver :
81+ class MappableDependencyResolver ( object ) :
8282 """Mix this into a ``DependencyResolver`` to allow mapping files.
8383
8484 Mapping files allow adapting generic requirements to specific local implementations.
@@ -176,7 +176,7 @@ def from_dict(raw_mapping):
176176
177177
178178@six .add_metaclass (ABCMeta )
179- class SpecificationAwareDependencyResolver :
179+ class SpecificationAwareDependencyResolver ( object ) :
180180 """Mix this into a :class:`DependencyResolver` to implement URI specification matching.
181181
182182 Allows adapting generic requirements to more specific URIs - to tailor name
@@ -188,7 +188,7 @@ def _expand_specs(self, requirement):
188188 """Find closest matching specification for discovered resolver and return new concrete requirement."""
189189
190190
191- class SpecificationPatternDependencyResolver :
191+ class SpecificationPatternDependencyResolver ( SpecificationAwareDependencyResolver ) :
192192 """Implement the :class:`SpecificationAwareDependencyResolver` with a regex pattern."""
193193
194194 @abstractproperty
@@ -220,7 +220,7 @@ def _expand_specs(self, requirement):
220220
221221
222222@six .add_metaclass (ABCMeta )
223- class InstallableDependencyResolver :
223+ class InstallableDependencyResolver ( object ) :
224224 """ Mix this into a ``DependencyResolver`` and implement to indicate
225225 the dependency resolver can attempt to install new dependencies.
226226 """
@@ -233,7 +233,7 @@ def install_dependency(self, name, version, type, **kwds):
233233
234234
235235@six .add_metaclass (ABCMeta )
236- class Dependency (Dictifiable , object ):
236+ class Dependency (Dictifiable ):
237237 dict_collection_visible_keys = ['dependency_type' , 'exact' , 'name' , 'version' , 'cacheable' ]
238238 cacheable = False
239239
0 commit comments