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Skilled craftsmen take pride in their own work.
Literal
Arm [possessive-の] good craftsman [topic-は] self [possessive-の] work [locative-に] pride [object-を] hold-[state-ている].
腕がいい ('has good arm') is an idiom meaning 'skilled, well-versed in one's craft' — using 'arm' metonymically for 'skill'. 工芸師 ('craftsman, artisan') is a formal term for someone who makes crafts. 誇りを持つ ('to hold pride') is the idiom for 'to take pride'. The ~ている form marks the ongoing state of pride.