feat: Lazily make mission-specific namespaces available under pyspedas

pyspedas/__init__.py

@@ -85,7 +85,6 @@
 # The code below is needed for backward compatibility, so users can continue to do things
 # like "from pyspedas.mms import mec" even after mms has been moved to the projects directory.
 
-import sys
 from importlib import import_module
 
 # List of submodules we want to make available under the pyspedas namespace
@@ -95,58 +94,19 @@
               'rbsp', 'secs', 'soho', 'solo', 'st5', 'stereo', 'swarm', 'themis', 'themis.state', 'twins',
               'ulysses'
               ]
-
-for submodule in submodules:
-    # Import the module from the new path
-    full_module_path = f"pyspedas.projects.{submodule}"
-    imported_module = import_module(full_module_path)
-
-    # Add it to sys.modules under the old path
-    sys.modules[f"pyspedas.{submodule}"] = imported_module
+
+def __getattr__(name):
+    if name in submodules:
+        return import_module(".projects." + name, __name__)
+    raise AttributeError(f"module {__name__!r} has no attribute {name!r}")
 
 # This set of imports is still needed for backward compatibility, when using fully-qualified
 # routine names in function calls, like "pyspedas.mms.mec()" rather than "pyspedas.projects.mms.mec()"
 
 # Make mission-specific namespaces available under pyspedas
-from .projects import ace
-from .projects import akebono
-from .projects import barrel
-from .projects import cluster
-from .projects import cnofs
-from .projects import csswe
-from .projects import de2
-from .projects import dscovr
-from .projects import elfin
-from .projects import equator_s
-from .projects import erg
-from .projects import fast
-from .projects import geotail
-from .projects import goes
-from .projects import image
-from .projects import kompsat
 # for backward compatibility
 from .projects.kompsat.load import load as kompsat_load
-from .projects import kyoto
-from .projects import lanl
-from .projects import maven
-# for backward compatibility
 from .projects.maven import maven_load
-from .projects import mica
-from .projects import mms
-from .projects import noaa
-from .projects import poes
-from .projects import polar
-from .projects import psp
-from .projects import rbsp
-from .projects import secs
-from .projects import soho
-from .projects import solo
-from .projects import st5
-from .projects import stereo
-from .projects import swarm
-from .projects import themis
-from .projects import twins
-from .projects import ulysses
 from . import vires
 from .projects import wind