typo fix and minor readability improvements
typo fix and minor readability improvements

tndatacommons/tndata_backend,izzyalonso/tndata_backend,tndatacommons/tndata_backend,izzyalonso/tndata_backend,izzyalonso/tndata_backend,tndatacommons/tndata_backend,tndatacommons/tndata_backend,izzyalonso/tndata_backend