Asked ChatGPT, got these answers but not sure I understand, anyone an expert here who can explain how we can estimate the amount of black holes outside of gravi

Asked ChatGPT, got these answers but not sure I understand, anyone an expert here who can explain how we can estimate the amount of black holes outside of gravitational lensing? "The distribution of black holes is inferred from their interactions, like accretion of matter and merging events, which emit observable signals. The total lensing exceeds what's expected from black holes and visible matter. Moreover, lensing often occurs where no black holes are detected, suggesting another form of mass—dark matter—is responsible. The distribution and amount of lensing provide crucial information that, when combined with other observations, suggests the presence of dark matter. Apologies for the confusion. The distribution of black holes is inferred from observable interactions like accretion and merging events, not primarily from lensing. The lensing exceeding what's expected from black holes comes from comparing the total lensing observed to what could be attributed to known black holes plus visible matter. There's more lensing than can be accounted for by black holes, hence suggesting dark matter as a probable cause."