fet: added docstrings for modules

Signed-off-by: Grzegorz Latosinski <glatosinski@antmicro.com>

scripts/python-skywater-pdk/skywater_pdk/simulation/analog/fet.py

@@ -17,6 +17,19 @@
 #
 # SPDX-License-Identifier: Apache-2.0
 
+
+"""Module for creating FET characteristics plots from bins.csv files.
+
+This module allows simulating FET cells and creating:
+
+* Id/W vs gm/Id
+* fT vs gm/Id
+* gm/gds vs gm/Id
+* gm/Id vs Vgg
+
+plots based on different FET length and width values from bins.csv file.
+"""
+
 import PySpice.Logging.Logging as Logging
 from PySpice.Spice.Netlist import Circuit
 from PySpice.Unit import u_V
@@ -235,7 +248,11 @@ def generate_fet_plots(
 def main(argv):
     import argparse
 
-    parser = argparse.ArgumentParser(prog=argv[0])
+    parser = argparse.ArgumentParser(
+        prog=argv[0],
+        description=__doc__,
+        formatter_class=argparse.RawDescriptionHelpFormatter
+    )
     parser.add_argument(
         'corner_path',
         help='Path to corner SPICE file containing FET definition',

scripts/python-skywater-pdk/skywater_pdk/simulation/analog/generate-fet-bins-plots.py

@@ -17,6 +17,14 @@
 #
 # SPDX-License-Identifier: Apache-2.0
 
+
+"""Creates plots for FET characteristics for FET cells in Skywater libraries.
+
+This script scans for FET cells in the Skywater PDK libraries and generates
+the FET cells using methods from the fet submodule.
+"""
+
+
 import argparse
 from pathlib import Path
 import sys
@@ -28,7 +36,11 @@ from fet import generate_fet_plots
 
 
 def main(argv):
-    parser = argparse.ArgumentParser(prog=argv[0])
+    parser = argparse.ArgumentParser(
+        prog=argv[0],
+        description=__doc__,
+        formatter_class=argparse.RawDescriptionHelpFormatter
+        )
     parser.add_argument(
         'libraries_dir',
         help='Path to the libraries directory of skywater-pdk',
@@ -61,7 +73,9 @@ def main(argv):
     )
     parser.add_argument(
         '--failed-inputs',
-        help='Path to files for which Symbolator failed to generate diagram',
+        help=('Path to an output file which will store all input filenames ' +
+              'for which ngspice failed to simulate'
+              ),
         type=Path
     )