environment setup

README.md

-test
+# Setup
+
+To install the Python virtual environment, run
+
+```
+conda env create --file environment.yml
+conda activate transcript-structure-generator
+```
+

environment.yml

+name: transcript-structure-generator
+channels:
+  - defaults
+  - conda-forge
+dependencies:
+  - python=3.9
+  - matplotlib
+  - pandas
+  - flake8-docstrings
+  - mypy
+  - flake8
+  - pytest
+  - coverage