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lines 5-18 of file: example/user/diff_constraint.py
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# {xrst_begin user_diff_constraint.py}
# {xrst_comment_ch #}
#
# Fitting with Constraints on Differences in Age and Time
# #######################################################
#
# Source Code
# ***********
# {xrst_literal
#     BEGIN PYTHON
#     END PYTHON
# }
#
# {xrst_end user_diff_constraint.py}