ArcMap script to copy a shapefile into a new smaller shapefile (in memory)

compressSHP.py

# Compress Shapefile by reducing Text Field lengths, dropping M and Z
# Unfortunately .management.AlterField only works for unpopulated text fields
# Process: Copy Table to NumPy array, Determine max length of text fields
# Create blank feature with previous as template, alter text field length
# Copy features to new feature class in memory
import arcpy.management as mg
import numpy as np

def compressSHP(inSHP, outSHP):
	fields = [f.name for f in arcpy.ListFields(inSHP) if not f.name == 'Shape']
	fields.insert(0,'SHAPE@')
	txtFields = [f.name for f in arcpy.ListFields(inSHP,field_type="String")]
	maxLens = np.array([0]*len(txtFields))
	for r in arcpy.da.SearchCursor(inSHP,txtFields):
		l = np.array([len(a) for a in r])
		maxLens = np.maximum(maxLens,l)
	meta = arcpy.Describe(inSHP)
	outSHP = mg.CreateFeatureclass("in_memory",outSHP,meta.shapeType,inSHP,
				       "DISABLED","DISABLED",meta.spatialReference)
	for txt, l in zip(txtFields, maxLens):
		mg.AlterField(outSHP,txt,field_length=l)
	ins = arcpy.InsertCursor(outSHP,fields)
	for rw in arcpy.SearchCursor(inSHP,fields):
		ins.insertRow(rw)